Police want to trace witnesses to a motorway collision involving a lorry and a car.
A white HGV, driven by a 43-year-old Swallownest man, is reported to have struck the back of a black Honda Civic, driven by a 33-year-old Woodseats man, between junctions 33 and 34 of the M1 at 4pm on Friday.
The lorry is believed to have been changing lanes at the time.
Officers want to speak to the driver of a white Mini who witnessed the collision but left before police arrived.
Anyone with information should call South Yorkshire Police on 101.