An NHM spokeswoman said: "A vehicle has collided with pedestrians near the Natural History Museum entrance at Exhibition Road". Armed police were deployed to the scene, which is also near the Science Museum, and the whole area was subsequently cordoned off.
Mark added: 'I think everyone seems to be just trying to carry on as normal because no one knows what is happening'.
The incident which occurred at 2.20pm immediately sparked a full-scale security lockdown in the area but police later confirmed the collision was not terror-related.
He said none of the head and leg injuries turned out to be serious and that most of the nine people who had been hospitalized have been discharged.
Eleven people were hurt in the collision although none of their injuries are believed to be life threatening or life changing.
Khan said details about the incident are still emerging and that he is in close contact with police and emergency services.
"A man (no further dets) has been detained at the scene".More news: Las Vegas massacre prompts more security at Chicago Marathon
The police said they were called at 14:21 p.m. local time to reports of a collision in Exhibition Road, South Kensington.
British Prime Minister Theresa May was being updated on the incident, according to her office. Police had said previously that the factor for this incident was under investigation.
Sky News said the police response to the incident was similar to that of the London Bridge terror attack in June, during which eight people were killed when a van drove into pedestrians and three men went on a stabbing spree.
A local worker said he saw two cars collide, with two men exiting one auto and removing a man from the other vehicle before pushing him on the ground.
She said: "I was getting off the Tube at South Kensington station, the doors opened and about 50 people came running down the Tube station escalator".
The auto ran into other vehicles and a large concrete barrier of the sort installed widely across central London after terrorist attacks on Westminster Bridge, Borough Market and The Mall where vehicles have driven into crowds.
In March, a man drove into pedestrians on Westminster Bridge, killing four people.