Detectives from the Roads and Transport Policing Command are appealing for witnesses following a fatal collision in north London.
Police were called at approximately 00:50hrs on Saturday, 6 January to reports of a collision between two Mercedes cars on Chamberlayne Road, NW10.
In particular, they would like to speak to a group of people who were walking along Chamberlayne Road, north bound, at the time of the collision.
Officers, the London Fire Brigade and the London Ambulance Service attended the scene.
The driver of one of the cars - a man believed to be aged in his 50s - was pronounced dead at the scene at 01:33hrs.
His next of kin are aware.
The driver of the second car stopped at the scene. He was arrested on suspicion of causing death by dangerous driving and drink driving, before being taken to a central London hospital for treatment to minor injuries. He has now been released under investigation.
Anyone with information is asked to contact the Serious Collision Investigation Unit based at Alperton on 020 8991 9555.