Russian rear Admiral Oleg Gurinov said the protest was made to the US-led coalition in Syria over actions by US troops.

TASS cited a senior Russian military official on Friday saying that “provocative” incidents had occurred in Syria’s northeastern province of Hassakeh where US forces have been deployed for several years, leading a coalition of local Kurdish troops battling against ISIL (ISIS) and its remnants.

“Provocative actions on the part of US armed forces units have been noted in Hassakeh province … the Russian side lodged a protest with the coalition,” Russian Rear Admiral Oleg Gurinov, head of the Russian Centre for Reconciliation of the Opposing Parties in Syria, told TASS.

Gurnivo said US troops had twice been spotted by Russian forces in areas that lay outside their agreed zones of operation, without giving details of timing.

“During joint Russian-Turkish patrols, the movement of two patrols conducted by the so-called anti-terrorist coalition were tracked along the non-deconfliction routes near Deiruna-Aga and Saramsak. The Russian side has protested to the coalition,” Gurinov said, according to TASS.

Russia – which together with Turkey is carrying out joint patrols in northern Syria – has agreed on special zones where the US-led coalition can operate as it takes on hundreds of ISIL fighters camped in desolate areas of Syria where neither the coalition nor the Syrian army exerts full control.

The US-led coalition has been engaged in Syria for almost eight years while Russia intervened in the Syrian Civil War in 2015, tipping the balance in President Bashar Al-Assad’s favour. Moscow has since expanded its military facilities in Syria with a permanent air and naval base.

Last week, the US carried out multiple air attacks in Syria against what it said were Iran-aligned armed groups, which the Pentagon blamed for a previous drone attack. US officials said the attack by the armed group killed a US military contractor, injured another, and wounded about a dozen US soldiers at a coalition base in the northeast of the country near Hassakeh city.

Pro-Iranian forces in Syria warned in an online statement signed by the Iranian Advisory Committee in Syria that they would respond to the US air strikes on their positions.

US military officials announced on Friday that the deployment of the George H W Bush carrier strike group would be extended after the drone by the Iranian-backed groups.

The decision likely means that the US strike group and its more than 5,000 US personnel, which are currently in the European Command operational area, will not be returning to the home port as scheduled.

“The extension of the George HW Bush Carrier Strike Group, inclusive of the USS Leyte Gulf, the USS Delbert D. Black, and the USNS Arctic, allows options to potentially bolster the capabilities of CENTCOM to respond to a range of contingencies in the Middle East,” US Central Command (CENTCOM) spokesperson Colonel Joe Buccino said in a statement.

News of the extended deployment first emerged a day after the Pentagon doubled its number of US troops wounded in the drone attack in Syria to 12.

The Pentagon estimated that eight people were killed during the retaliatory US air attacks against targets it claimed had links to Iran.

Both the Iranian and Syrian foreign ministries slammed the US air attacks that Washington said had targeted the strategic region of Deir ez-Zor bordering Iraq.

In a statement last week, Iranian foreign ministry spokesperson Nasser Kanani said the US “terrorist” attacks hit civilian targets and constituted a violation of international law and Syrian sovereignty.

“The US claims that it is present in Syria to fight Daesh [ISIL] that itself had a major role in creating is just an excuse to continue its occupation and loot Syria’s national wealth, including its energy resources and wheat,” he said.

Kanani also said Iran only has military advisers on the ground in Syria at the request of its government.

The Syrian foreign ministry criticised the “brutal” US attacks that it said killed several people and amounted to a violation of its territorial integrity and promised to “end the American occupation”.

The White House has said the attacks on its forces would not force a pullback of the US from Syria.