ISIS has beheaded British aid worker David Haines. The video features the terrorist known as Jihadi John, and includes a threat to kill another British hostage, .\r
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Warning: This video may be disturbing. After showing a clip of British Prime Minister David Cameron, ISIS releases A Message to the Allies of America, which .\r
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ISIS has beheaded British aid worker David Haines. The video features the terrorist known as Jihadi John, and includes a threat to kill another British hostage, .\r
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Warning: This video may be disturbing. After showing a clip of British Prime Minister David Cameron, ISIS releases Another Message to America and Its Allies, .\r
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