Two people died when the car in which they were travelling went out of control in Bradford.
The man and the woman, both in their 20s, were passengers in a Renault Scenic which overturned in Tong Lane at Tong at 0130 BST on Sunday.
Emergency services released them from the wreckage but they were found to be dead.
The driver of the car left the scene but was arrested a short time later.
He has been arrested on suspicion of causing death by dangerous driving.
Tong Lane has been closed while investigations continue.