Transcript for Dire Situation as ISIS Threatens Another Western Hostage
We know there are at least two Americans being held by this group and tonight, right here, you're going to see in the tapes what investigators have also noticed. ABC's chief investigative correspondent Brian Ross studying the tapes, too. Reporter: Isis has already selected its next victim. 47-year-old british aid worker Alan henning. Today, current and former officials said it will be very difficult to stop them. We have neither the intelligence nor the access to these hostages to be able to rescue them. Reporter: Just as no one could stop the cycle of executions, about once every two weeks, of James Foley, Steven sotloff and over the weekend, british aid worker David Haines. All purportedly beheaded by the same masked man with a british accent, who taunts his victims and their countries. This british man has to pay the price. David has been murdered in the most brutal way imaginable by an organization which is the embodiment of evil. Reporter: By its own admission, the U.S. Has been late to appreciate the escalating threat from Isis. Until recently, U.S. Intelligence had not closely tracked the movements of its top leaders. Nor the Americans recruited to fight there, who it is feared could return home for jihad. Do we know Isis that well yet? I think the answer is knno. Reporter: U.s. Drones and satellites are now overhead, looking for clues, as at least five more western hostages are under threat of execution by Isis. But based on the video from this weekend, analysts say Isis is working hard to hide its location. Gone are the road, rock and plant landmarks from previous videos. All that can be seen in the background now is a stark desert sand dune. The attorney general, Eric holder, said today the U.S. Can and must do better to stop Americans who want to join Isis. He announced a series of pilot programs and a white house S summit on the urgent issue. So urgent, that the summit won't take place until next month. Brian, thank you. We move on now to another
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