Announcer: Starting right now on ABC's "This week," breaking overnight, Isis claims it's executed another American hostage. We have team coverage of the horrific new videotape and what it means in the... See More
Announcer: Starting right now on ABC's "This week," breaking overnight, Isis claims it's executed another American hostage. We have team coverage of the horrific new videotape and what it means in the battle against the brutal terror group. Ferguson on edge again. Brand-new images of officer Darren Wilson hours after the shooting of unarmed teenager Michael brown. A grand jury decision now days away. What the new video reveals. How will the community react? Immigration showdown, the president vowing to act on his own. How far will he go? And 60 days away, a top Hillary ally says her 2016 decision is coming soon. From ABC news, "This week with George stephanopoulos" begins now. Good morning. I'm Martha Raddatz, and breaking right now, it has apparently happened again. A third American murdered by Isis in a disturbing and graphic tape released just hours ago. The terror group claims it beheaded 26-year-old peter kassig, a former army ranger from Indiana captured while working with an aid group in Syria. Chief investigative correspondent Brian Ross joins us now with the latest. Good morning, Brian. Well, good morning, Martha. U.s. Intelligence officials are working at this hour to formally authenticate that video, but the gruesome images posted by Isis leave little doubt about what happened. A former U.S. Soldier in Iraq, kassig went back to the mideast to Syria as an aid worker featured two years ago by CNN. We each get one life and that's it. You get one shot at this. Reporter: During captivity kassig converted to Islam and changed his name from peter to abdul-rahman. From their home in Indiana, his parents, Paula and ed kassig, launched a campaign pleading for their son to be set free. We implore those who are holding you to show mercy and use their power to let you go. Reporter: Islamic groups around the world joined in and even Al Qaeda called for the release of kassig. But with this morning's video, it was clear there would be no mercy. The 16-minute propaganda production first showed the mass beheadings of 16 Syrian soldiers, the Isis fighters actually appearing unmasked and then in the last two minutes, the same masked man with a british accent seen in previous execution videos appears with kassig's severed head at his feet. He claims he is in the Syrian city of dabiq and addressed president Obama saying "We are burying the first American crusader in dabiq eagerly waiting for the remainder of your armies to arrive." Kassig was captured in October of last year. In a letter smuggled out by a fellow prisoner, kassig wrote this to his parents, "If I do die, I figure that at least you and I can seek refuge and comfort in knowing that I went out as a result of trying to alleviate suffering and helping those in need." Kassig's parents only learned of the video in the last few hours and told us this morning they are waiting for government confirmation before they say anything. The white house says if confirmed, "We are appalled by the brutal murder of an innocent American." Martha. As we all are. Thanks, Brian. Let's bring in Matt Olsen who was the director of the national counterterrorism center until just this past September. What stands out in this tape to you? It does seem different in several ways. The biggest difference, Martha, is that we don't have what appears to be peter kassig speaking on the tape and he's not shown alive as the other hostages who were executed. And what does that tell you? Well, it's hard to say right now. It's possible, of course, that he wouldn't cooperate and speak on the video, but, you know, again at this point right now what's happening inside the government is that analysts in the intelligence community are looking very closely at this tape to determine whether it's authentic and to really examine every detail of it to see what we can learn. It seems like there is more detail in this tape, where the executioner is standing in a city and that you could tell more from this tape but it's also bolder, it's very much in your face about that. Yeah, a couple of things, first, we don't know when the tape was made and, again, that's one of the things that analysts will be looking at. Certainly looking at right now as we speak and through the day. There are details that can be reviewed. In terms of the boldness of the tape, Martha, it does have threats, again, threats to our personnel, American soldiers in Iraq, as well as -- In fact, it says we will slaughter your soldiers and then begin to slaughter your people on the streets. Are they capable of coming to the homeland? We've seen this before a couple of times now from Isis in retaliation for what we're doing, sort of vague threats like take this to the west or slaughter your people as it says in the tape on your streets. You know, the short answer to your question is, no, not on any sort of significant scale. We do have concerns that they're capable of small-scale attacks. Or inspiring people to carry it out who already live here. Exactly, inspiring people through this type of propaganda, perhaps people who are mentally ill or deranged finding this to be somehow attractive. Quickly, Matt, it does appear to be the same british executioner. Do we know who he is and does this put more pressure on the U.S. And others identifying him so he becomes an international fugitive? Well, he does have that british accent, does seem to be the same person and, you know, obviously inside the government working very hard to exactly identify him and anything we can learn about him. Okay, thanks very much for joining us, Matt. Sure. Thank you.
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