Ain Issa, located on the strategic M4 highway that connects northeast Syria, is held by the Syrian Democratic Forces (SDF), a Kurdish-led alliance of militias which handed the Islamic State (ISIS) militant group a territorial defeat with U.S. military support.

A rebel source with the so-called Syrian National Army told Reuters the faction seized some farmland after mounting an attack at the edge of the town.

Shelling hit parts of Ain Issa and the M4 but SDF forces were thwarting the attack, Reuters said on Friday, citing an SDF commander who spoke with local Kurdish media.

The town has been bombarded by Turkey-backed fighters since early December. The attacks have led to an agreement between the SDF and Russia last week for Russian and pro-Syrian government forces to establish military positions in the area to deter further violence.

The clashes overnight come as Turkey reportedly abandoned several observation posts in northern Syria it deemed untenable.

Reporter's code: 50101