dagan mcdowell, buck sexton, that does it for me.ened? purported beh allan henning, so far it looks real. >>> this is a fox news alert. some horrific and very sad noew to report tonight. there's a video on the internet and it purports to show the beheading of allan henning. our chief intelligence continue catherine herridge has seen the tape and she joins us now with more. >> reporter: within the last hour, u.s. officials confirming they are ammizing the video. i viewed it and it's significantly shorter than the previous isis videos at just under two minutes, it begins with a british news report over the image of the british