A 20-year-old man has died after the car he was driving crashed into a tree.
South Yorkshire Police said the crash happened in Ulley near Rotherham shortly after 01:15 GMT.
The car, a black Suzuki Jimny, left the road before hitting a tree on Pennyhill Lane between the M1 and Wood Lane, the force added.
Anyone in the area at the time, who witnessed the collision or saw the vehicle beforehand, should contact police on 101.
Officers are also keen to see any relevant dashcam, doorbell, or CCTV footage.
The family of the man, who is believed to be from Sheffield, is being supported by trained officers, police said.