Eyewitnesses describe a chaotic scene after London terror attack

Witnesses to a terrorist attack in which an assailant apparently plowed a car into pedestrians and an officer was stabbed near the Houses of Parliament in London described a chaotic scene this afternoon, with injured people lying sprawled in all directions.

At least one victim was killed in the attack, according to the BBC.

More details about what transpired are not yet known, but Richard Tice, an eyewitness, told ABC News that he saw police steering people away from the area where the attack took place.

Another eyewitness told the BBC that someone driving a car on Westminster Bridge appeared to hit bystanders and that paramedics were treating people on the ground.

Journalists inside Parliament told The Associated Press they were told to stay in their offices.

British lawmaker Grant Shapps said on Twitter that he was walking through the cloisters of the House of Commons and heard "four gunshots."

Witness Rick Longley told the Press Association that he saw a man stab a policeman outside Parliament, the AP reported.

"We were just walking up to the station, and there was a loud bang, and a guy, someone, crashed a car and took some pedestrians out," he said. "They were just laying there, and then the whole crowd just surged around the corner by the gates just opposite Big Ben. A guy came past my right shoulder with a big knife and just started plunging it into the policeman. I have never seen anything like that. I just can't believe what I just saw."

Radoslaw Sikorski, a former foreign minister of Poland, posted a video on Twitter that seems to show people lying injured in the road on Westminster Bridge.

Sikorski, now a senior fellow at Harvard's Center for European Studies, wrote, "A car on Westminster Bridge has just mowed down at least 5 people."