There have been reports of a collision and a number of injured pedestrians in Exhibition Road, near the Natural History Museum.
There is a large emergency presence as part of the road was cordoned off at around 3pm on Saturday (October 7).
Several pedestrians have been injured after a car hit people near the Natural History Museum in London, police say.
The Metropolitan Police said one person had been detained following the incident at 2.30pm in Exhibition Road in South Kensington.
Video footage that emerged on Twitter showed a man being restrained on the ground.
Police at the scene said that the pedestrians’ injuries were minor.
Police said inquiries are under way to establish the circumstances and any motive.
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A shocked visitor who was leaving the Natural History Museum as the incident happened.
“I could see a car diagonally across the road, looking like it was going into one of the boulders on the side of the road, and I could see a crowd of people around what was clearly one or two people on the pavement,” she said.
She added there were now armed police at the scene.
“We have had lots of police coming onto the scene, helicopters above, and I can see an ambulance which is definitely having someone put in, but it isn’t clear how bad that injury is.”
Exhibition Road is an area popular with tourists as it is home to the Natural History Museum, the Science Museum and the Victoria and Albert Museum.
An eyewitness who was walking to the Science Museum said: “When waiting for the light, we heard what I thought was gunshots and saw a car drive over the pavement. We just ran. My friend dived on the floor and cut her hands.
The woman, who asked to remain anonymous, said: “When it calmed down we walked back to where we’d been and saw a gentleman on the floor being restrained by police.”
Connor Honeyman, from Essex, who was in the queue for the museum, said: “We heard a horrible thudding noise and a car engine. Everyone started running and screaming inside.
“We ran in, everyone was following us, and then all the security guards ran out and they closed the main entrance. There was much confusion before the police got there.”