Transcript for Driver arrested after crashing into barriers at British Parliament

Overseas a driver plowing into pedestrians and slamming into a barrier in London. Counterterrorism is on the scene. James Longman is on the scene. We've been moved a few hundred meters back from the houses of parliament. You can see where the car slammed into the security barrier. Just around here you see columns of police. We've seen police presence growing all morning. Reporter: This morning central London on lockdown. After a car deliberately crashed into a security barrier outside Britains houses of parliament during rush hour. That would appear to be the car. Reporter: The bbc catching this video of the car speeding up before it crashes. He was going maybe 40 to 50 miles an hour, maybe more. Didn't swerve into it. It was a direct hit. Reporter: One witness said a group of cyclists were waiting at a light when a car ran into them. They said the driver made no attempt to slow down. I think a cyclist was injured. Reporter: Two people were rushed to the hospital when police swooped in to arrest the suspect. There are dozens of police cars and overhead helicopters. They closed the Westminster subway station and cornered off a huge area of the capitol. The incident reminiscent of last year's car crash by parliament. We heard the suspect is in his late 20s. Police say they haven't found any weapons in his car. He's not cooperating with police. They're trying to find a motive. David. James, thanks. Back here at home the flash flood emergency across the northeast.

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