A police officer suffered leg injuries in West Hampstead on Thursday after officers stopped a BMW they believed was "driving suspiciously".
Met officers were on a routine patrol at around 10.25pm when they spotted a blue BMW in Netherwood Street in the Webheath estate, which runs between Kilburn High Road and Sheriff Road.
The Met said a police officer was trapped between the car and a stationary police vehicle and injured as its driver attempted to reverse away.
Three men – aged 24, 26 and 33 – have been arrested. Police said a fourth man fled the scene.
The officer was taken to hospital with leg injuries but has since been discharged.
Camden and Islington police commander Ch Supt Raj Kohli, said: "My thoughts are with my injured colleague and his family."
He appealed for anyone who witnessed the incident or who has dashcam footage to come forward.
Call police on 101 and quote CAD 7709/06May, tweet @MetCC or call Crimestoppers on 0800 555 111.
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