In the area of clashes in Deir Ezzor, partially controlled by the US-backed, Kurdish-led Syrian Democratic Forces (SDF), a "cautious calm" prevailed on Wednesday after army forces staved off the advance of SDF-allied militants, according to the Syrian Observatory for Human Rights monitor.

The clashes since Tuesday morning, accompanied by US air strikes, were in a cluster of seven government-controlled villages located east of the Euphrates -- the only ones outside SDF control on the river's eastern bank in the area, the Observatory told AFP.

The Britain-based Observatory reported "16 dead including two civilians" since the SDF-allied Deir Ezzor Military Council launched the attack on army forces and allied pro-Iran militia.

The toll includes 11 soldiers, and three from the Deir Ezzor Military Council, the Observatory added.

Control of Deir Ezzor province is split between the SDF to the east of the Euphrates River, and the Syrian army to the west.

According to the Observatory, the small cluster of villages where fighting took place on Tuesday is strategically important, being a direct point of contact with SDF-held areas.

The villages are also located near a US military base in the Conoco gas field.

Observatory chief Rami Abdel Rahman told AFP that "the seven villages are the first line of defence for the city of Deir Ezzor, which has been the centre of gravity for Iranian influence since IS was expelled."

Controlling the villages also reduces the threat posed by pro-Iran groups to the Conoco base, he added.

The Observatory said US forces, who lead an international anti-IS coalition, also carried out air strikes in Deir Ezzor province on Tuesday.

The Pentagon said US forces destroyed truck-mounted rocket launchers, a tank and mortars in eastern Syria, without specifying where or saying who the weapons belonged to.

Iran-backed groups have repeatedly targeted US forces in Iraq and Syria in response to Washington's support for Israel in the Gaza war since October 2023.

*This story was edited by Ahram Online.