Transcript for New arrests in wake of London terror attack

see last night. Something that all of Britain needed this morning, London bridge now open again after Sunday's attack in the heart of London. Here is what we know. ISIS claiming responsibility for the deadly terror attack that killed at least seven people. That rampage lasting just eight minutes before the three suspects were eventually shot dead by police. This is the third deadly terror attack in the uk since March. Which is why the prime minister speaking out so strongly. We have team coverage this morning starting with our chief foreign correspondent Terry Moran on the scene in London where there were more arrests overnight. Good morning, Terry. Reporter: Good morning, George. Well, on this Monday morning, on the surface, anyway, it looks as if London is almost back to Normal. The roadways are full of traffic, the subways are crowded but look again. And you see the flowers at the makeshift memorials that have cropped up at these sites. You see new barriers along the sidewalks on the bridges to protect against another bridge attack. This is the second one. And intense police activity as they hunt down possible collaborators. This morning, police launching more raids in the same area of east London where they've arrested 12 so far. It's all going on right now. People running. I don't know out of where. Reporter: This new video capturing frightened residents fleeing restaurants and bars shortly after a hail of gunfire. Get down, get down. Reporter: The chaotic moments of terror that shook the city began before 10:00 P.M. Saturday. A white van heading south on London bridge suddenly swerves off the road up on the sidewalk and accelerates running down pedestrians leaving them broken and bloodied on the pavement. Get back. It just reminds me of something like 9/11. Reporter: The van came to a halt at the end of London bridge just steps from the bustling borough market packed with bars and restaurants filled on a busy Saturday night. We were in lockdown because there's just been an attack. Reporter: Three men jumped out armed with long knives and began slashing and stabbing the innocent. Saw the knife and just didn't turn around again. They were there to do one thing only, to kill people, stab them, stab them to death. Reporter: At 10:0 the first emergency calls came in. Police swarm the attack scene. Terrified locals watching from windows. It took police just eight minutes to corner the suspects then gunfire. Oh, my god. Reporter: All told, 50 shots were fired by eight officers. Hear shooting. I'm trying to keep myself safe. Reporter: Seven people killed. The apparent suicide vests worn by the attackers were found to be fakes. Overnight president trump at a gala in Washington making his first televised remarks since the attack. America sends our thoughts, our prayers and our deepest sympathies to the victims of this evil slaughter, this bloodshed must end. This bloodshed will end. Reporter: And this morning, prime minister Theresa may capturing the wartime mood here. This was an attack on London and the United Kingdom but it was also an attack on the free world. ??? Reporter: In the wake of the attack the police presence doubled at the site of Ariana grande's one love Manchester benefit concert, a so-called ring of steel encircling the venue keeping the sold out crowd of 50,000 safe. And in the wake of this attack

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