Transcript for Battle against ISIS in Syria

Hi this is ABC news live on the impanel. In Northern Iraq we're now getting more details about that deadly bomb blast just across the border in Syria that killed four US service members we now know that they were from different branches of the US military. They will are described by ABC sources as part of an intelligence gathering group. Apparently there were on a family roots CNBC and the rest on the was frequent sit by the US military also by US senate says when they came to visits in northern Syria. Apparently an ice is Paul Mullen US now believes that it wasn't us his bomber detonated his suicide best outside the hotel and we've seen some of the horrific pictures that. Of what then transpired this is the deadliest attack against the US military. Throughout six participation in the war here in Syria. But it also underlines the threat that on sees continues to represent not a single looser rules so here in Iraq. These walls are these huge concrete walls and there is blast walls the reason that will post here a round this complex is specifically to deter. Crisis suicide bombers. But we know that the US servicemen didn't have that kind of Force Protection all not day. The fighting still continues on the front lines in this area and here in Iraq. And despite president trumped we've seen only last month that prices have been defeated and that the US troops was roaring. This attack on the lines and they still represents a very great threat for ABC news alive on the impanel. In Northern Iraq.

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