"ISIL members executed at least 22 persons with firearms or knives, after taking control of Shuyukh outside the town of Jarabulus" in Aleppo province, Rami Abdel Rahman, head of the Syrian Observatory for Human Rights, told AFP. Among those killed were "at least 12 armed rebels," he said.
ISIL seized Jarabulus, near the northern border with Turkey, from the rebels last month. At the beginning of January, a number of rebel groups joined an offensive against ISIL, accusing it of atrocities against people from their own ranks and among civilians.
At least 3,300 persons have been killed in that fighting, according to the Britain-based Observatory, which relies on activists and other sources inside Syria.
ISIL is accused of kidnapping scores of people, among them rival rebels, activists, foreign journalists and humanitarian workers.