The Strand has been closed in both directions after a "serious collision", but police said the incident was not thought to be terrorist related.
Police were called to the Covent Garden area on reports that a taxi had hit pedestrians.
Transport for London said the road was closed from both directions at Southampton Street due to a serious collision.
Police on scene in #CoventGarden following a collision with pedestrians in Southampton Street. Not thought to be terrorist related.— Metropolitan Police (@metpoliceuk) November 1, 2017
Police and firefighters were at the scene dealing with serious injuries, and police said the driver of the taxi had been detained by police.
Police on scene at Covent Garden dealing with serious injury accident involving a taxi. Not Terror related. Further updates will follow.— MPS Westminster (@MPSWestminster) November 1, 2017
The London Ambulance Service said four patients were treated in total - a man was treated for a serious leg injury and taken to a trauma centre while two others were treated for minor injuries and taken to hospital and a fourth was checked over at the scene.
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