ISIS Beheads U.S. Hostage Peter Kassig

Like a wounded animal lashing out in fury, ISIS is betraying hints of desperation in its latest video, which purportedly shows the aftermath of the beheading of U.S. hostage Peter Kassig, analysts said Sunday.

And if there's news worse than the apparent brutal death of Kassig, it's that we should expect even more vicious videos to come from the group, also known by the acronym ISIL, said Haras Rafiq of the Quiliam Foundation, an anti-extremist think tank.

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