Detectives are appealing for witnesses - or anyone with dash cam footage - to come forward following a collision that has left a man with life-threatening injuries.
Police were called at approximately 3.40am on Sunday to reports of a collision involving a motorcycle in Southwark Street, SE1.
The police and the London Ambulance Service attended and the rider of the motorcycle, a 27-year-old man, was taken to an east London hospital for treatment.
"At this stage his condition is being treated as life-threatening," said a police spokesman.
"It was initially thought that the motorcycle had been involved in a collision with a car that had failed to stop at the scene.
"Detectives have carried out fast paced enquiries throughout the day, and it has now been confirmed that this car was not involved.
"Enquiries still continue to trace any direct witnesses to the collision."
Officers from the Serious Collision Investigation Unit are asking for anyone with images, dash cam footage, or information regarding the moments leading up to the collision, to call 101 or tweet @MetCC quoting reference Cad 1221/09Feb.
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