Beirut - A U.S.-supported Syrian rebel group said Wednesday it will open an investigation into the beheading of a Syrian boy on spy accusations, calling it an “individual mistake” that does not represent the overall policies of the group.

The Nour el-Din al-Zinki group, a relatively moderate group that fights the Syrian government and the Islamic State group, condemned the beheading which was captured on video and triggered an instant backlash against the group.

It is not clear who the boy was or why he was beheaded on camera. He was identified by activists on social media as Mahmoud Issa, a 12-year-old Palestinian. The Syrian government also denounced the killing in a statement to the United Nations, saying the boy was a Palestinian from a refugee camp near Aleppo.

The incident allegedly occurred in Handarat, near Aleppo, on Tuesday. A young boy is seen on the back of a pickup truck surrounded by armed men who accuse him of being a spy and a member of the Quds Brigade, a pro-government Palestinian militia. He is then beheaded with a knife by one of them.... Read More: VIN