U.S. armored vehicles were seen on Thursday near the Syria-Turkey border in a part of northeastern Syria where they had not been observed since early October when Washington announced the withdrawal of American forces, according to a witness and Reuters video footage.

A military source from the Kurdish-led Syrian Democratic Forces (SDF) described the movement as a patrol running between the towns of Rmeilan and Qahtaniyah, which is 20 km (12 miles) to the west. The source said it would "not be a one-time" event.

The witness saw the U.S. military vehicles outside the town of Qahtaniyah, roughly 6 km (4 miles) south of the border.