A Syrian Islamist rebel group released footage on Wednesday purportedly showing the mass execution of captured Islamic State (IS) militants.
Prisoners are seen kneeling in front of militants from the Damascus-based rebel coalition Jaish al Islam, with chains tied around their necks and wrists, before being shot in the back of the head. In a role reversal, the Jaish al Islam militants are dressed in orange jumpsuits similar to those in which IS typically dresses victims in its own execution videos.
Speaking directly to the camera, one of Jaish al Islam's members accuses IS of supporting Syrian President Bashar al-Assad, saying "They wreaked havoc on our people in the liberated areas and cut the supply route of jihadists, supported the Assad regime in the name of our religion." The group claims to have "declared war" on IS.
The video also claims that "four senior IS commanders held a confidential meeting with four other high-ranking officers of the Syrian intelligence in Damascus."
Last week IS released a video in which it decapitated 12 members of rival rebel groups, including at least three Jaish al Islam fighters and one from local al Qaeda affiliate Jabhat al Nusra.
Jaish al Islam, a member of the Islamic Front coalition, is based in Damascus's Douma and Ghouta neighborhoods and is the dominant opposition power in the region. It was formed from dozens of local Islamist and Salafist rebel factions and is led by the charismatic Zahran Alloush. Like other Islamic Front members, it's widely believed to be backed by Saudi Arabia.
While not as extreme as IS, Jaish al Islam adheres to a hardline interpretation of Sunni Islam, although Alloush has sought to portray the group as part of Syrian society and distance himself from IS-style sectarian beliefs in recent interviews.
In 2013 it was accused of taking part in a sectarian massacre in the southern Syrian town of Adra targeting members of the Druze ethnoreligious group and the Alawite Shiite Muslim sect. Alloush has previously said in a video that he would "wash" Syria of Rafida (the Arabic for "rejectors", but used by some Sunnis, especially Salafists as a pejorative term for Shias). The language used in Wednesday's execution video is also sectarian in nature, using a derogatory term for Alawites and accusing IS of siding with Shias.
IS first appeared in Syria around April 2013. It initially attempted to merge with local al Qaeda affiliate Jabhat al Nusra, but al Nusra leadership spurned its advances and IS has since clashed with both Islamist rebel factions as well as more moderate opposition groups.
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