Two police officers were left in a critical condition after they were struck by a car as they were making their way back to their vehicle.
The two Police Constables, based at Brent borough in north west London, were returning to their marked car park on the A406 North Circular Road near Brent Park, Neasden, at around 3.40am on Sunday, when the collision occurred, Scotland Yard said.
The driver of the Maerati - a man aged in his 50s - was arrested at the scene on suspicion of dangerous driving and failing to provide a specimen of breath. He has been taken to a north London police station where he remains in custody.
The officers are in a critical condition in hospital with their next of kin in attendance.
The two officers, one male and one female, were taken to hospital along with a female occupant of the car.
The male officer suffered serious injuries, while female officer sustained a number of fractures. Her condition is described as serious but stable.
Road closures were put in place while emergency services dealt with the incident. All cordons have now been lifted.