Islamist militants and their local supporters have killed at least 22 people in a village in northern Syria near the Turkish border, opposition activists said on Wednesday, Reuters reported.
The Syrian Observatory for Human Rights monitoring group quoted residents in Shuyukh, 100 km (65 miles) northeast of Aleppo, as saying that militants from the Islamic State of Iraq and the Levant (ISIL), had killed 12 fighters from rival rebel groups and at least 10 local tribesmen, including a 16-year-old.
The British-based watchdog, which has a network of sources across Syria and opposes President Bashar al-Assad, said the men had been executed by gunfire and knives. It said at least nine other villagers were missing and suspected to have been killed.
Media activists circulated online a list of people they said were victims. They named 20 people killed and nine missing, and said four bodies had been thrown into the Euphrates River.
"Residents of Shuyukh betrayed the mujahideen. Then ISIL stormed into the area," said an opposition activist who runs a Facebook page for the Jarablus area, which includes Shuyukh.
He said ISIL, an al Qaeda breakaway group, had participated in the attack, but that local men had led it.
The Facebook page for Jarablus published a photo of what appeared to be the bodies of five men on a dirt path running through a field, as bystanders inspected the scene.
Reuters was unable to verify the reports independently due to media restrictions in Syria.
ISIL has battled other Islamist rebel groups in the area in the past few weeks. A car bomb it detonated in Jarablus in January killed at least 26 people.
More than 3,300 people have been killed in fighting between ISIL, most of whose fighters are foreign, and other insurgents, including al Qaeda's official Syria branch, the Nusra Front.
According to the Observatory, more than 140,000 people have died in Syria's three-year-old conflict, which began as peaceful protests against four decades of Assad family rule but turned into an armed insurgency after a crackdown by security forces.