Transcript for New details on London terror attack

Also this morning we are learning new details about the terror attack and new rays overnight. ISIS has claimed responsibility for the attack but -- and authorities say they know the identities of the attackers, of course, that attack killed seven people, injured dozens more before police took down the three terrorists. And let's go back now to our chief foreign correspondent Terry Moran on the scene for us in London for new details coming in right now. Good morning, Terry. Reporter: Good morning, Amy. Well, as londoners get back to work the police investigation is moving at high speed. Overnight those two more raids in the same general eastern suburban area where 12 were arrested over the weekend, one man was led away. Prime minister Theresa may saying that all three names of the attackers are known to authorities. The big question now, how long had authorities known about these attackers who drove that van over the London bridge, then descended with long knives into the borough market slashing and stabbing people. 21 victims remain in critical condition, a sign of just how horrible their wounds were. Meanwhile, londoners getting back to work here, prime minister may saying this was an attack not just on the city of London, not just on the united Kingdom but on the free world and there is a sense here of responsibility to stand up to these attacks, three in three months and to carry on and keep calm as the British will. Amy. All right, Terry Moran, we appreciate it. Thanks so much.

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