Transcript for Chemical weapons inspectors headed to site of suspected chemical attack

Mean, across the border in syriani Russia now Ving its military assets, and what assorces are Doi right now in advance possible strikes. ABC's James Longman also here in beer tonight. Very tonight, signsussia and Syria are bracing forattack. The Syrian militaryaking defensive action,itioning war planes and moving equipment to pro tm fromng ted. Ssians on the move, O. These satellites appear to show Russian naval ships disappearing from this port in Syria. Russia today saying they will protect their people on th ground. Tonight,ossible evidence in that Hor suspected chemical attack. Fficials areaware of a W report fro Syrian mal activide most ofhe ims symptoms, say they're consistent with chlor exposure. Some showingymptoms consistent with a NER agent. An attack Russia and Syria say R happened Let'ring in James longma and James is here inbeirut obviously, with us tonight. Know that chemical weapons inspectors who are here in this Ty are preparing now to visit that site WHE alleged attak place? Reporter: That's right, David. They are due to begin their work saay, but it's been a ll week since that attack too place, and since Russian troops have been in the ar therere real concerns about the kind O evidence they're going toe LE to gather. Evidence thatht haven taken away. Jalongman tot, thank you.

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