The British Isis killer known as "Jihadi John" may have a body double, according to a new video analysis, which also suggests that American aid worker Peter Abdul-Rahman Kassig was beaten before his death.
Analysts who have conducted close-up examinations of the footage of Kassig's severed head say the hostage's face shows a large bruise above his left eye, suggesting he put up a struggle.
Freeze-frame analysis also appears to show that while there only appear to be 18 or 19 jihadists and victims in the main part of the video, there are in fact 22. In addition to the execution of Kassig, the film also shows a mass execution of Syrian regime officers and pilots.
As well as "Jihadi John", who plays the central role, one other is wearing a balaclava, a fact that seems to be deliberately hidden as it is visible only from a single "screen grab".
That has led the analysts to speculate that he might be intended to be a double for the chief executioner, perhaps to confuse drone surveillance. There seemed little reason to have another masked man on hand, given the fact that all the other men present show their faces except for Jihadi John.