BEIRUT (Reuters) - Islamic State launched an attack on Friday on positions held by the U.S.-backed Syrian Democratic Forces (SDF) in southeastern Syria and the U.S.-led coalition mounted air strikes in the area, an SDF official said.

Islamic State used car bombs and dozens of militants in the attack near Abu Khaser village in the Hajin area of southeastern Syria, where the SDF and coalition are battling to wipe out the last Islamic State pocket east of the Euphrates River, the SDF official Mustafa Bali said.

Fierce clashes were continuing, Bali said in a text message to Reuters.