U.S.-led coalition forces returned fire after being repeatedly shot at near Manbij in northern Syria, where they are patrolling near areas held by Turkish-backed rebels, coalition spokesman Colonel Ryan Dillon told Reuters on Tuesday.

“Our forces did receive fire and return fire and then moved to a secure location,” he said by phone.

The coalition has told Turkey to tell the rebels it backs there that firing on U.S.-led coalition forces “is not acceptable”, Dillon said.

“Our overt patrols that have been conducting patrols in that area to keep tensions down received fire multiple times over the course of the last two weeks,” Dillon said.

“We let our counterparts in Turkey know this and we continue to conduct these patrols but are always prepared and ready to defend ourselves in that area.”