Terrorists from the "Islamic State" (ISIS) group battled rebel forces, including Islamists, on Sunday for a series of key villages in northern Syria, the Syrian Observatory for Human Rights said, according to AFP.
The four villages in the northern province of Aleppo lie along the rebels' supply line from Turkey, which is a major backer of Syria's opposition.
"ISIS is trying to seize control of these villages from rebels to cut their supply route between Aleppo city and its outskirts, and the town of Azaz," a rebel bastion near the border, said Observatory head Rami Abdel Rahman.