Ah okay, the version given by the Syrian-American commentator on the news earlier today was suggesting that he was accusing IS of perpetuating the attack, then sending their own medics and film crews in to the area in a staged rescue operation for propaganda purposes.
It is an old adage that the first casualty of war is the truth, and it is likely that we may never be able to definitively apportion the blame on either side in this instance, while huge numbers of Syrians suffer and die.
Truly tragic, and unrelentingly horrific.