BEIRUT - Fighters from an al-Qaida-linked Syrian rebel group beheaded an allied commander whom they mistook for a pro-government fighter, activists said on Saturday.
It was the latest excess attributed to the aggressive and radical Islamic State of Iraq and the Levant. While allegations of ISIL attacks on civilians and infighting with more moderate rebels are commonplace, this time it appears to have killed a member of another hard-line group, Ahrar al-Sham. While that groups isn't as radical as ISIL, it's still considered to be among the more hard-line organizations fighting to overthrow President Bashar Assad.
It's unclear whether the incident will cause a falling out between the groups, who have co-operated together in the past. A militant website reported that the ISIL acknowledged the incident and asked for calm, saying that mistakes occur in wartime.
The incident happened in the northern city of Aleppo, where two fighters were videotaped displaying the severed head to a crowd on Wednesday. The men claimed the head belonged to an Iraqi Shiite fighter allied to the government of Bashar Assad, but residents later recognized it as belonging to a rebel commander.
Activists said the ISIL fighters found the wounded rebel in a hospital after a battle with government forces on Wednesday. As he emerged from anesthesia, he called out the names of saints recognized by Shiites, an Islamic sect whose members have largely sided with Assad, one of the activists said.
Assad is an Alawite, a member of a Shiite offshoot sect, and Shiite militiamen from Lebanon and Iraq have fought alongside his forces against largely Sunni rebels.
The incident underscores the sectarian nature of Syria's war and the chaos among rebel groups battling Assad's forces in their quest to overthrow the government.
"The medics knew he wasn't a Shiite, but they were too scared to stop them," said one of the activists.
The next day, two young ISIL rebels were videotaped brandishing a man's head.
"This is an Iraqi Shiite who fights for the army of Bashar (Assad)," one man shouted, holding the man's head in one hand, and a knife in the other.
But residents recognized the head as belonging to Ahrar al-Sham leader Mohammed Marrouche, known by his nom de guerre Abu Abdullah al-Halaby, one activist said.
The Aleppo-based activists asked to remain anonymous for fear of retribution by ISIL. One activist said he spoke to medical workers in the hospital to confirm the information. They confirmed the authenticity of the video.
The account was given by two Aleppo-based activists and Rami Abdurrahman of the British-based Syrian Observatory for Human Rights. The Observatory obtains its information from a network of activists on the ground.
The next day, some residents held a demonstration outside ISIL's Aleppo headquarters, demanding a halt to beheadings, one activist said.
Furious Ahrar al-Sham partisans posted a video calling ISIL fighters "idiots" and noted that rebel fighter Marrouche had longish hair and a full bushy beard typical of conservative Sunni Muslims. "The Shiites do not do this," they sarcastically noted. Others posted a video showing Marrouche calling for his group and ISIL to work together.
On Saturday, a pro-rebel website published a poster attributed to Ahrar al-Sham that showed a close up of the two ISIL rebels, with the word "wanted" emblazoned across their faces. "Two killers wanted for judgment in the Islamic court," read the poster.
It was not possible to confirm the authenticity of the poster, nor to contact either Ahrar al-Sham or ISIL fighters for comment.
An Islamic scholar, Omar al-Qahtani, identified as an ISIL member, later issued an explanation of the incident that stopped short of an apology. It was quoted on a website that frequently carries al-Qaida statements.
Syria's three-year-old uprising began as demonstrations but evolved into an armed rebellion after government forces attacked demonstrators.
The Islamic State of Iraq and the Levant, a recent addition to the rebel movement, has a reputation for attracting foreign fighters and for aggressiveness that goes beyond even the other hard-line groups.
The group has taken the lead in battles against Assad loyalists, but has also cowed activists and other rebel groups who they see as opposing their plans to implement their extreme version of Islamic law in rebel-held areas.