Pacific

The use of high-altitude balloons is becoming ever-more routine for U.S. Army units in the Pacific. The service is pushing to deploy more of these lighter-than-air platforms as a key component of a new persistent surveillance and reconnaissance ecosystem across the region. The same kinds of balloons could also perform these and other missions, including communications relay, electronic warfare, or even launching kinetic strikes, around the globe. This is all underscored by a recent contracting notice about the potential purchase of commercial-off-the-shelf high-altitude balloons, sensor packages, and datalinks connected to SpaceX’s space-based Starlink network.

“This is a commodity requirement for commercial-off-the-shelf (COTS) or modified-COTS high-altitude balloon systems and associated equipment,” according to the contracting notice from the Army’s 921st Contracting Support Battalion, which was posted online earlier this week. “The required supplies and software licenses will be delivered to locations within the INDOPACOM AOR [U.S. Indo-Pacific Command area of responsibility] (specifically Hawaii).”

The notice stresses that the 921st is currently only conducting “market research” and that a “full and open competition” could follow, but is not guaranteed. The battalion is headquartered in Hawaii, but is the Army’s main contracting arm in the Pacific, and has elements spread across the region.

The “commodity requirement” the 921st outlined in the notice includes a call for 15 high-altitude balloons, five each of three different sizes (12-, 16-, and 24-gore). The term gore here refers to the individual segments making up the balloon’s exterior. A greater number typically translates to a larger inflated volume, and, by extension, to higher altitude capability and/or payload capacity. The contracting notice mentions a desired “burst altitude (90k–120k ft class)” for the 24-gore type, but does not otherwise lay out specific performance or payload requirements for any of the balloons.

The notice also includes a call for several different sensor packages, described as follows:

• Five “EO/IR [Electro-optical/infared]” types with “resolution (1080p/4K/MWIR/LWIR); gimbal stabilization; telemetry bandwidth (Starlink/LTE/MPU5); power draw; onboard processing; environmental hardening.”
• Five “Long Wave Infrared” types with “Spectral band (8–14 μm); NETD sensitivity (≤50 mK ideal); optics (germanium lenses, FOV options); thermal stabilization; data interface (Ethernet/SDI/USB-C).”
• Seven “Electronic Sensing” types capable of providing “(RF/EM/atmospheric/SIGINT); frequency coverage; antenna configuration (omni/directional/array); data logging (local vs. downlink); EMI shielding for high-altitude ops.”

The Army would also want eight payload buses with Starlink connectivity and MPU5 radios, as well as seven more with Starlink only. This separately speaks to the growing prevalence of Starlink, and its government-focused cousin, Starshield, across the U.S. military, something TWZ just recently highlighted.

There is also a call for helium and other ancillary items to complete the full package. The contracting notice does not say whether or not these balloons and other equipment would be intended for operational use, training, and/or supporting test and evaluation activities. TWZ has reached out to U.S. Army Pacific (USARPAC) for more information.

Use of balloons by the Army and other branches of the U.S. military, as well as other countries globally, both historically and as part of more contemporary activities, is not new. This is something TWZ had been calling attention to for years before a Chinese spy balloon passing over parts of the United States and Canada in 2023 thrust the topic into the public consciousness. China has used balloons and other kinds of lighter-than-air craft for intelligence-gathering and other purposes across the Pacific. The use of high-altitude balloons as launch platforms for swarms of drones and other payloads has also been an active area of development in China. This is something the U.S. military and others have also been experimenting with.

Modern high-altitude balloons can stay aloft for days, weeks, or even months on end. There are designs that can be precisely navigated to areas of interest and then hold their general position in spite of prevailing winds, moderating their altitudes to remain on station persistently for very long periods at a time. As the recent contracting notice makes clear, these balloons also have sufficient payload capacity to act as intelligence, surveillance, and reconnaissance (ISR) platforms, as well as signal relay nodes. They could perform other missions, too.

In 2024, the Army made a particularly public demonstration of the value of high-altitude balloons in modern operations during Exercise Valiant Shield 24. Balloons fitted with “electromagnetic spectrum sensors and radio networking equipment” were part of the kill chain in a live-fire test of Precision Strike Missile (PrSM) short-range ballistic missiles against a moving target ship. Valiant Shield 24 involved forces deployed to various locations across the Pacific.

Also in 2024, the Army’s Communications-Electronics Command (CECOM) put out a contracting notice seeking details about prospective small radars and signals intelligence suites for use on high-altitude balloons. The mention of radars here highlighted how balloons could provide another layer of ground-moving target indicator and synthetic aperture radar imaging (GMTI/SAR) capability.

CECOM’s request for information was specifically tied to an experimentation and demonstration effort called High-Altitude Platform-Deep Sensing (HAP-DS). The Army said at the time that the goal was for HAP-DS to feed into a larger program called the High-Altitude Extended-Range Long-Endurance Intelligence Observation System (HELIOS).

The Army has continued to expand its experimental efforts since then with a clear eye toward future operational capabilities. Last year, the service disclosed plans to launch as many as 100 balloons, and maybe even more, in an upcoming exercise.

“Our primary goal is to demonstrate autonomous swarming capabilities that generate a persistent, cost-effective presence in the stratosphere,” Andrew Evans, Director of Strategy and Transformation with the Office of the Deputy Chief of Staff of the Army, or G-2, told Breaking Defense in an interview in August 2025. “Once operationalized, this type of capability will enable us to conduct a range of military operations including enhanced intelligence, surveillance, and reconnaissance (ISR), the extension of tactical communications, and the rapid reconstitution of on-orbit capabilities when space is denied or degraded.”

At that time, Evans also highlighted how large groups of high-altitude balloons networked together could help provide resiliency against potential losses, including just due to bad weather.

Large numbers of balloons would be needed to provide wide-area persistent coverage for ISR and other missions. They could also be used to create mesh and other kinds of hub-and-spoke-type networks, which could be especially valuable if communications assets in low Earth orbit (LEO) are threatened.

Earlier this year, the Army shared that it had established a new schoolhouse for high-altitude balloon training, including a basic skills course for “High-Altitude Soldiers”, at Joint Base Lewis-McChord in Washington State. As of March, Army Green Berets, as well as Air Force personnel from weather units, and even individuals from unnamed civilian agencies, were said to have gone through the training program.

The Army has said that the training program includes the use of 16-gore high-altitude balloons – one of the types mentioned in the recent contracting notice – made by a company called Urban Sky. This is from a line of what the firm markets as “Microballoons,” which can be deployed by relatively small teams in minutes. Urban Sky says its 16-gore design can soar at altitudes up to 70,000 feet and carry payloads weighing up to 50 pounds. The company also offers a payload called Wallabee that combines “EO/IR imaging, signals intelligence, and communications downlink in a single package,” again fully in line with the “commodity requirement” recently outlined by the 921st Contracting Support Battalion.

Other companies, including Aerostar and the Sierra Nevada Corporation, also offer broadly similar designs that can be configured for ISR, signal relay, and other missions.

Raven Aerostar – Thunderhead Balloon System

“Routine events such as the AHABC [Army High-Altitude Basics Course], conducted here at home station, have enabled our unit to both maintain individual proficiency and provide more repetitions to leaders to sharpen their HA skills,” Army Capt. Tyler McWilliam, described as a “High-Altitude Planner,” said in an official release in March. “The plan for the future is to offer more High-Altitude Basic Courses for service members in other units to spread High-Altitude knowledge across the joint force.”

The Army has made no secret about the overarching end-goal of its current high-altitude balloon plans. The service is moving “forward in building a persistent, all-domain sensor architecture for the Indo-Pacific theater,” the March press release stated right up front.

The complete architecture is also set to include other components, including the Army’s new High Accuracy Detection and Exploitation System (HADES) ISR business jets. Glider-like drones also designed to operate in the stratosphere are something else the service has been actively experimenting with in recent years. As noted, like China and others, the U.S. military has also been exploring high-altitude balloons as launch platforms for swarms of drones deep inside hostile territory. This, in turn, has opened the door to the potential for using balloons to launch kamikaze drones and other kinds of munitions. They could carry electronic warfare payloads or seed small sensors on the ground, too.

All this being said, despite the Army’s clear support for high-altitude balloons, and years of experimentation, the service still has yet to put them into more widespread operational use. There is a distinct and continued disparity here compared to China’s extensive use of balloons and other lighter-than-air craft in the Pacific.

The capabilities that high-altitude balloons stand to offer the U.S. military could be very relevant for providing persistent surveillance and supporting other missions elsewhere globally, too. U.S. Central Command has previously highlighted interest in using lighter-than-air platforms to help meet high demand for ISR capacity across the Middle East.

The recent contracting notice, as well as the establishment of the new training programs at Joint Base Lewis-McChord, do show that the Army is pressing ahead with its plans to make high-altitude balloons a more regular aspect of its operations, especially in the Pacific.

Contact the author: joe@twz.com

Boeing is now conducting test flights of its MQ-28 Ghost Bat drone out over the Pacific from the U.S. Navy’s base in Point Mugu, California. The company says its main goals are to demonstrate the maturity of the design, originally developed for Australia, and promote export sales. The specific choice of testing location also seems notable given Boeing’s involvement in the Navy’s still-evolving carrier-based Collaborative Combat Aircraft (CCA) plans.

The MQ-28 has now flown at least three times within the Point Mugu Sea Range off the coast of southern California, according to a Boeing press release. The expansive range is routinely used for a wide array of research and development and test and evaluation activities, as well as training. Naval Air Station Point Mugu, part of Naval Base Ventura County, sits right on the coast, surrounded by farmland, with direct access to the range and minimal risk to bystanders. Its location makes it well suited for uncrewed aircraft operations, and it already has a major role in this regard in relation to the MQ-4C Triton and managing target drones.

MQ-28 first international flights

“This testing shows the MQ-28’s ability to operate seamlessly from allied facilities, which helps Boeing demonstrate the aircraft’s maturity and potential export opportunities to international customers outside Australia,” per the press release from Boeing. “Tests at Point Mugu validate autonomous systems while following required airspace, range safety and regulatory approvals.”

Boeing also described this as “MQ-28’s first international operation in allied airspace,” but it is unclear when the first sortie from Point Mugu occurred.

In December, the Pentagon released a video of Secretary Pete Hegseth visiting Naval Air Station Point Mugu with an MQ-28 clearly visible in the background. However, the drone seen in that footage also had an early-style paint scheme with high-visibility orange trim. Pictures and video that Boeing released along with its announcement of the Point Mugu Sea Range flight testing show a Ghost Bat with a two-tone gray livery. It also has an infrared search and track (IRST) sensor system in the nose, something not seen on the example in the Hegseth video. The MQ-28 is a highly modular design, with the nose section designed to be readily swappable.

There have also at least been indications of Ghost Bat flight testing in the United States in the past. The U.S. Air Force previously said it had made use of at least one MQ-28 to support advanced uncrewed aircraft and autonomy development efforts.

Boeing itself released a picture of an MQ-28, again with the early paint scheme and no IRST, at MidAmerica Airport outside of St. Louis, Missouri, back in 2023. In that instance, the Ghost Bat was displayed alongside the demonstrator the company had been using to support the development of the MQ-25 Stingray tanker drone for the Navy.

How many Ghost Bats are currently in the United States is unknown. TWZ has reached out to Boeing for more information.

The MQ-28 has been flying in Australia since 2021, two years after the design was first shown publicly. Boeing’s subsidiary in Australia had already been working on the design before then under the Royal Australian Air Force’s (RAAF) Airpower Teaming System (ATS) program. To date, RAAF has received eight Ghost Bats in a pre-production Block 1 configuration.

Boeing is now working to build the first of a batch of nine Block 2 drones, which are seen as an intermediate stepping stone to an operational Block 3 version. The Block 3 type is expected to be substantially larger and have greater range. It will also feature an internal weapons bay that could accommodate a single AIM-120 Advanced Medium Range Air-to-Air Missile (AMRAAM), two GBU-39/B Small Diameter Bombs (SDB), or equivalently sized stores.

Boeing and the RAAF have already conducted at least one live-fire AIM-120 launch from a Block 1 Ghost Bat, with the missile having been carried aloft on an external pylon under the drone’s fuselage.

Uncrewed MQ-28 Ghost Bat showcases its combat capability

Block 1 MQ-28s have also been used to demonstrate other important capabilities in testing to date. This includes crewed-uncrewed teaming with RAAF E-7A Wedgetail airborne early warning and control aircraft and F/A-18F Super Hornet fighters. The ability to operate from allied facilities that Boeing says the Point Mugu sorties demonstrate could be valuable just for Australia for future coalition operations.

MQ-28, Wedgetail, Super Hornet: Drone Intercept Behind-the-Scenes

Boeing has also been open about its interest in pursuing sales of the MQ-28 outside of Australia. The company has publicly named Japan as a potential customer and has said it is exploring potential opportunities with other unnamed countries in the Indo-Pacific region. In March, Boeing Australia announced a partnership with Rheinmetall in Germany to pitch the Ghost Bat to that country’s armed forces. A carrier-capable version of the design with a tail hook has been pitched to the United Kingdom in the past, as well.

This latter point brings us to what is largely absent in Boeing’s announcement about MQ-28 flight testing from Point Mugu: the U.S. Navy.

In September 2025, the Navy confirmed that it had awarded Boeing, as well as Anduril, General Atomics, and Northrop Grumman, contracts to develop “conceptual” carrier-based CCA drone designs. At that time, the service also announced that Lockheed Martin was under contract for work on an accompanying common control architecture.

In April 2025, Navy Capt. Ron Flanders, public affairs officer at the Office of the Assistant Secretary of the Navy for Research, Development & Acquisition (RDA), had also told TWZ directly that “the U.S. has expressed strong interest in leveraging the MQ-28’s AI-driven autonomy and modular design for future air combat operations.”

As mentioned, Boeing is also developing the MQ-25, a production representative version of which just flew for the first time in April. Beyond the important aerial refueling and other capabilities the Stingray is set to bring to the Navy’s carrier air wings, the service routinely describes it as a “pathfinder” to future uncrewed aviation capabilities.

MQ-25A Stingray First Flight

All this being said, the Navy’s CCA plans are still very much evolving. The service, by its own admission, has been trailing behind the U.S. Air Force and the U.S. Marine Corps in the development of CCA-type drones.

Flight testing now from Point Mugu is certainly an important development for the MQ-28 program as a whole, and one Boeing hopes could open the door to new opportunities for the Ghost Bat. Whether or not that includes deeper U.S. Navy involvement remains to be seen.

Contact the author: joe@twz.com

May 24 (Asia Today) — South Korea is preparing to publicly unveil a development roadmap for a nuclear-powered attack submarine program after the successful Pacific deployment of the domestically built Dosan Ahn Chang-ho submarine, according to military and defense officials.

The move signals Seoul’s effort to strengthen what officials describe as the strongest conventional strategic deterrence available to a non-nuclear weapons state in response to North Korea’s advancing nuclear and missile capabilities and growing maritime competition in the region.

Senior military officials said the Ministry of National Defense and the Defense Acquisition Program Administration have completed technical reviews for a South Korean nuclear-powered submarine program and are now coordinating with related ministries, including the Foreign Ministry, on a diplomatic and regulatory strategy.

The report follows the recent Pacific deployment of the 3,000-ton Dosan Ahn Chang-ho submarine, which sailed about 14,000 kilometers, or 8,700 miles, from Jinhae through Guam and Hawaii using only domestically developed lead-acid batteries, diesel engines and an air-independent propulsion system.

South Korean officials said the deployment significantly reduced the need for snorkeling operations, in which submarines surface or raise air intake masts to recharge batteries, and demonstrated the vessel’s long-duration underwater operational capability and hull durability.

Officials also said the submarine successfully demonstrated stable operation of its submarine-launched ballistic missile vertical launch system in rough Pacific conditions. The Dosan Ahn Chang-ho class is the world’s first diesel-electric submarine class equipped with vertical launch tubes for submarine-launched ballistic missiles.

Defense experts said the mission simultaneously highlighted the operational limitations of conventional diesel submarines and the strategic advantages of nuclear propulsion.

While diesel-electric submarines must operate at relatively slow underwater speeds to maintain endurance, nuclear-powered submarines can remain submerged for much longer periods and travel underwater at speeds exceeding 40 kilometers per hour, allowing broader operational flexibility, officials said.

The foreign affairs and security publication The Diplomat reported Thursday that South Korea’s pursuit of a nuclear-powered submarine would become “a major test case of non-nuclear deterrence” for a country that does not possess nuclear weapons.

Chung Sung-chang, head of the Korea Nuclear Strategy Forum and a senior researcher at the Sejong Institute, said the submarine under discussion would be a non-nuclear attack submarine that would not carry nuclear weapons.

Chung said South Korea plans to retain the hull design and submarine-launched ballistic missile strike capability proven through the Dosan Ahn Chang-ho program while replacing the diesel propulsion system with a small nuclear reactor.

He said South Korea should first publicly present its nuclear submarine development roadmap before negotiating a bilateral nuclear submarine cooperation agreement with the United States and securing approval from the U.S. Congress.

Chung also said Seoul would need a separate agreement with Washington to secure low-enriched uranium fuel for naval reactors derived from downgraded highly enriched uranium.

Officials are reportedly studying the AUKUS security partnership among the United States, Britain and Australia, under which Australia received access to nuclear-powered submarine technology while remaining within the international nonproliferation framework.

South Korean officials said the success of the Dosan Ahn Chang-ho deployment demonstrated that the country’s technical preparations for a future nuclear-powered submarine program had reached a mature stage, shifting the focus toward diplomatic negotiations and international coordination.

— Reported by Asia Today; translated by UPI

© Asia Today. Unauthorized reproduction or redistribution prohibited.

Original Korean report: https://www.asiatoday.co.kr/kn/view.php?key=20260524010006872

May 8 (Asia Today) — South Korea’s first domestically designed 3,000-ton submarine has completed a long-distance Pacific deployment as Seoul seeks to strengthen its bid for Canada’s next-generation submarine procurement program.

The South Korean Navy said the Dosan Ahn Chang-ho departed Pearl Harbor-Hickam in Hawaii on Friday with two Canadian Navy submarine personnel aboard and is scheduled to arrive at Esquimalt Harbor in Victoria, British Columbia, in late May.

The submarine left Jinhae Naval Base on March 25 and traveled through Guam and Hawaii before heading toward Canada.

The deployment is seen as a major test of the submarine’s endurance, reliability and operational performance, as South Korean shipbuilders compete for Canada’s submarine project, estimated at about $42 billion.

The Dosan Ahn Chang-ho is expected to travel up to about 18,600 miles round trip, much of it independently. Defense officials say the mission is intended to demonstrate the submarine’s long-range capabilities, quiet operation, onboard living conditions and air-independent propulsion system.

Two Canadian Navy personnel, Maj. Britany Bourgeois and Petty Officer Jake Dixon, joined the submarine for the final leg from Hawaii to Canada.

The submarine is expected to take part in joint training with the Canadian Navy after arriving in late May. The exercises are expected to focus on anti-submarine warfare and interoperability.

Canadian officials are expected to assess whether the South Korean submarine meets key requirements for long-range patrols and operations near Arctic waters.

The Dosan Ahn Chang-ho will later participate in the U.S.-led Rim of the Pacific exercise, known as RIMPAC 2026, alongside South Korea’s next-generation Aegis destroyer Jeongjo the Great.

South Korea’s participation is expected to highlight its growing ability to operate with U.S. and allied naval forces in complex maritime environments.

Canada’s submarine procurement program calls for the acquisition of 12 submarines. South Korean shipbuilders Hanwha Ocean and HD Hyundai Heavy Industries are competing against Germany’s Thyssenkrupp Marine Systems for the contract.

Defense analysts say the Pacific deployment gives South Korea an opportunity to demonstrate proven operational capabilities directly to Canadian officials rather than relying only on written proposals or technical specifications.

The Dosan Ahn Chang-ho is the lead vessel of South Korea’s KSS-III Batch-I class. The submarine has an underwater displacement of about 3,700 tons, is 83.5 meters long and was designed and built in South Korea.

South Korean defense officials say the deployment marks a milestone for the country’s submarine program and reflects the expansion of the Navy’s operating range from coastal waters to the open ocean.

If South Korea wins the Canadian contract, it would mark the largest single defense export deal in the country’s history.

— Reported by Asia Today; translated by UPI

© Asia Today. Unauthorized reproduction or redistribution prohibited.

Original Korean report: https://www.asiatoday.co.kr/kn/view.php?key=20260508010001855

Los Angeles is a city rich with regional specificity when considering the cuisines of Asia. When someone asks for a restaurant recommendation for “Korean food” or “dumplings” or “Thai,” I encourage them to be more specific. Are you in the mood for xiao long bao, mandu, gyoza or momos? You want to know where to get barbecue in Koreatown? Those sizzling grills crowded with galbi, while dependably righteous, only scratch the surface of the breadth and depth of Korean cuisine in what is home to the largest Korean diaspora outside of Korea.

There are omakase experiences for every price point. Cramped izakayas. A restaurant where the sole speciality is lamb prepared in the style of the Uyghur people of China’s Xinjiang province. Pho parlors and banh mi shops with pâté-smeared baguettes. Sunny Taiwanese breakfast restaurants slinging steaming bowls of congee and tightly wrapped fantuan.

AAPI-owned restaurants act as the vital centers of countless communities around the city. The San Gabriel Valley, Westminster, Little Bangladesh, Koreatown and so many more. These are places that are both hubs for thriving immigrant communities and sought-after dining destinations.

Here’s a list of 20 AAPI-owned standouts from our most recent guide to the 101 Best Restaurants in the city. — Jenn Harris

April 30 (UPI) — The Union Pacific and Norfolk Southern corporations announced Thursday a new merger proposal after a federal regulator rejected their initial plan in January.

The two companies applied for a merger in July, seeking to create the United States’ first transcontinental freight railroad.

The Surface Transportation Board rejected the proposal saying the application was incomplete.

A statement from the two companies said they resubmitted the application with “additional analysis” indicating cost savings for customers and improvement to the U.S. supply chain. It said the deal would take 2 million truckloads off the nation’s roadways and save $3.5 billion each year.

“After completing the additional work requested by the STB, the facts remain clear: This merger enhances competition and delivers real public benefits that make America’s supply chain stronger, Union Pacific CEO Jim Vena said in a statement.

The new submission includes traffic data from each of the six North American Class I railroads instead of sample data provided by the STB, the companies said.

The STB will have 30 days to review the new application.

April 27 (UPI) — The U.S. military has killed another three men in its latest attack targeting suspected drug-trafficking boats in the eastern Pacific, U.S. Southern Command announced late Sunday.

It was the 54th strike in the Trump administration’s violent anti-drug smuggling campaign that has killed at least 185 people since early September, according to UPI’s tally of publicly released data. At least 57 boats have been destroyed in the attacks in the eastern Pacific and Caribbean.

SOUTHCOM has announced each strike on social media, accompanied by a short black-and-white aerial video of the attack, showing the boat erupting in flames.

As with the previous strikes, SOUTHCOM said in a statement that the boat it attacked Sunday “was transiting along known narco-trafficking routes in the eastern Pacific and was engaged in narco-trafficking operations.”

The Trump administration claims the vessels are operated by 10 drug cartels and gangs that President Donald Trump has designated as terrorist organizations since returning to office, but has yet to provide evidence.

Trump argues the use of deadly force is warranted as the United States is in “armed conflict” with those organizations, but his administration has come under mounting accusations of conducting extrajudicial killings.

The strikes have been repeatedly condemned and their legality questioned by Democrats and human rights organizations, who accuse the Trump administration of violating international and maritime law by using the military to conduct law enforcement drug operations.

Ben Saul, the United Nations’ special rapporteur on counterterrorism and human rights, chastised the Trump administration last month for “responding with lawless violence that flagrantly violates human rights, in its phony war on so-called narco-terrorism.”

The attacks are not permissible law enforcement action in self-defense, authorized under the law of the sea, in national self-defense or under international humanitarian law, he said.

On Thursday, 125 humanitarian, human rights, peacebuilding and other related organizations from around the world called on all states to “immediately cease or refrain from supporting U.S. extrajudicial killings.”

The letter warned that states could be held legally responsible for aiding or assisting the United States by sharing intelligence as well as providing access to military bases and logistical support with the U.S. military.

The groups argue that the consequences of these killings are being felt throughout the hemisphere.

“Families awaiting the return of their loved ones may never know what happened to them and have no access to recourse,” the organizations said in their open letter.

“Coastal communities have witnessed human remains washing up on shore and fear for their lives when they trade and fish, sowing psychological trauma and undermining livelihoods.”

The Department of War has released a video it says shows US forces boarding a sanctioned tanker in the Asia Pacific region as part of their efforts to disrupt vessels providing support to Iran.

The killings mark the fourth US deadly strike in the past four days on vessels in the eastern Pacific Ocean.

The US military has killed four more people in its fourth deadly attack on vessels in the eastern Pacific Ocean over the past four days.

US Southern Command (SOUTHCOM) announced the attack in a social media post on Tuesday, alongside a video that showed a stationary boat with outboard engines being hit by a missile and exploding into a huge ball of flames.

SOUTHCOM, which is responsible for US military operations in Latin America and the Caribbean, claimed that the four people killed were “narco-terrorists”, but provided no evidence to support its claims.

Justification for the lethal attack, according to SOUTHCOM, was due to intelligence – details of which were not provided – that confirmed that “the vessel was transiting along known narco-trafficking routes in the eastern Pacific and was engaged in narco-trafficking operations”.

The latest killing of people on board vessels in international waters in the eastern Pacific Ocean and Caribbean brings the overall death toll to at least 175 since early September, when US President Donald Trump ordered the attacks to stop what the White House claims are Latin American cartels transporting drugs to the US.

Tuesday’s killings came after two people were killed in a US strike on Monday, and five people were killed in two separate strikes on Saturday, also in the eastern Pacific.

The Associated Press news agency reported that the US coastguard has suspended a search for one survivor from the two attacks reported on Saturday.

International legal experts and rights groups say the US military campaign amounts to “extrajudicial killings” in international waters and that the attacks have targeted civilian fishing boats.

Legal experts have said that if some vessels were involved in drug trafficking, those on board should face the law, rather than deadly attacks.

Critics have also questioned the effectiveness of the US military operation in part because the fentanyl behind many fatal overdoses in the US, which Trump has used to justify his campaign, is typically trafficked to the US over land from Mexico, where it is produced with chemicals imported from China and India.