The international coalition said its forces in north-east Syria on Wednesday (February 12th) confronted gunmen with live fire after one of its patrols came under attack near the city of Qamishli.

"Coalition forces, conducting a patrol near Qamishli, Syria, encountered a checkpoint occupied by pro-Syrian regime forces," coalition spokesman Myles Caggins said.

"The patrol came under small arms fire from unknown individuals. In self-defence, coalition troops returned fire," he said.

Caggins said the patrol returned safely to base after the situation was "de-escalated".

According to the Syrian Observatory for Human Rights, pro-regime elements residing in the village of Khirbet Amo tried to block the passage of a US military patrol, firing in the air.

This prompted a response from US troops, who killed a regime loyalist in the clash, the Observatory said. The coalition did not report such a casualty.

Khirbet Amo is among the few areas in the largely Kurdish-held north-east controlled by pro-regime forces.

US troops in the region operate as part of the international coalition fighting the remnants of the "Islamic State of Iraq and Syria" (ISIS).

They routinely carry out patrols in the area alongside their Kurdish allies.