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Islamic State militants fighting in Iraq and Syria released a video on Thursday that they said shows British journalist John Cantlie in captivity. In the video, Cantlie says he will soon reveal "facts" about the group to counter its portrayal in Western media.

The Islamic State, which controls territory in Syria and Iraq, has already beheaded two American journalists and one British aid worker in recent weeks in what it said was reprisal for U.S. air strikes against it in Iraq.

But in the new roughly three-minute video posted on social media sites, the man identified as Cantlie appears in good health and promises to "convey some facts" in a series of "programs," suggesting there would be further installments.