Transcript for Military and hazmat crews continue to investigate alleged Russian poisoning attack

investigators in hazmat suits descending on a cemetery in England looking for clues. Trying to find out who poisoned a former Russian spy and his daughter. Both visited the cemetery recently. Both are fighting for their lives. Reporter: Paula and Dan, good morning. Investigators are retracing every single step that sergei skripal and his daughter, yulia, may have taken. Investigators believe they may have come this week. Chemical weapons specialists out in Salisbury. Military-trained in chemical W warfare also involved. 180 troops sent in. Hazmat crews placing a tent over the the graves of sergei skripal's wife and his son. Released to the uk in a spy swap in 2010. For the last eight years, he's made this city home. He's kept a relatively low profile. Reporter: And the the big question is how was the poison deliver snd and when did skripal and his daughter, yulia, come in contact with it? They had lunch and then collapsed on this park bench. The toxin. A nerve agent described as very rare. That could only have been produce bid a few laboratories in the world. Is it scarier to think that the Kremlin might have decided to order a nerve gas attack on British soil snr on it is scarier to think that somebody might have done this sort of on their own? Reporter: And very scary, of course, either way. The suspicion is squarely on the Russians. They have done it before. Later today, a big emergency meeting. The second one this week. Dan? Paula? That have done it before. Thank you very much. We appreciate you reporting this morning.

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