Dozens of trucks, some carrying armoured vehicles, departed the base at Qasrak in Hasakah province on Monday morning, witnesses said. Reuters footage later showed the trucks moving along a highway on the outskirts of the city of Qamishli.

The U.S. military’s Central Command did not immediately respond to an emailed request for comment.

A full withdrawal from Qasrak would still leave the U.S.-led coalition with a base in Rmelan, also known as Kharab al-Jir, near the Iraqi border.

Qasrak has been a main hub for the U.S.-led global coalition fighting Daesh in Syria, where U.S. troops deployed over a decade ago, partnering with the Kurdish-led Syrian Democratic Forces (SDF) against the jihadist group.

Neither the Syrian defence ministry nor the SDF responded to requests for comment.