Tensions on the Korean Peninsula have increased as North Korean leader Kim Jong Un accelerates weapons development.

North Korea has fired “several” cruise missiles from its west coast into the sea, according to South Korea.

Seoul’s Joint Chiefs of Staff (JCS) said the missiles were fired on Wednesday morning.

“Our military detected several cruise missiles launched by North Korea towards the Yellow Sea at around 7:00 am today [22:00 GMT on Tuesday],” the JCS said in a statement.

“The detailed specifications are being closely analysed by South Korean and US intelligence authorities.”

Pyongyang, which is under strict United Nations sanctions over its nuclear weapons programme, has continued to conduct weapons tests this year including a solid-fuelled hypersonic ballistic missile and the test of a purported nuclear-capable underwater attack drone.

Cruise missile tests are not banned under the UN sanctions but the JCS said it was monitoring further activities by North Korea. Cruise missiles tend to be jet-propelled and fly at a lower altitude than more sophisticated ballistic missiles, but analysts say they could pose a risk to South Korea and Japan because they are harder to detect by radar.

Tensions on the Korean Peninsula have increased in recent months as North Korean leader Kim Jong Un continues to accelerate his weapons development and issue provocative threats of nuclear conflict with the United States and its allies in the region.

Japan, South Korea and the US, meanwhile, have been expanding their combined military exercises – which Kim portrays as invasion rehearsals – and sharpening their deterrence strategies built around nuclear-capable US assets.

The latest launches came as the South Korean Navy’s special warfare unit was taking part in training on the east coast near the border with North Korea.

The 10-day training, which ends on Thursday, is designed to strengthen operational readiness, the JCS said, following North Korea’s recent military activities.

Leader Kim Jong Un has also abandoned any goal of unification with South Korea, which he has now designated as a “primary enemy“.

Kim might also have ordered the demolition of a 30-metre (100 ft) high Pyongyang monument that symbolised the goal of reconciliation with South Korea.

NK News, an online publication that monitors developments in the country, said satellite imagery taken on Tuesday showed The Monument to the Three Charters for National Reunification, known informally as the Arch of Reunification, was no longer there.

Depicting two women holding aloft an emblem of a united peninsula, it was completed across a key Pyongyang road in 2001. NK News said Kim had called it an “eyesore” during this month’s meeting of the Supreme People’s Assembly.