At 5.35 p.m. on Sunday, 31 July, emergency services were called to a report of a car colliding with a pedestrian in Uxbridge Road, Pinner.
Officers and ambulance personnel responded to the scene. The pedestrian, a man in his eighties, was pronounced dead at the scene.
The driver of the car pulled over to the side of the road.
Anyone who has yet to speak with the police is asked to dial 101 and enter the reference number 5393/31july.