An 18-year-old Coodanup man remains in critical condition in Royal Perth Hospital after falling from a moving car in Baldivis on Friday night.
It's understood a 17-year-old boy from Wellard on his learner's permit and his friends were driving a silver Toyota Aurion sedan at about 9.50pm, before stopping to speak with the 18-year-old who is known to him.
Three members of the group, including the Coodanup man, then climbed onto the outside of the car.
As the driver started to drive off, the 18-year-old fell from the car and is believed to have struck his head on the road.
St John Ambulance attended the scene and took the injured man to Rockingham General Hospital.
He was later transferred to Royal Perth Hospital due to the serious nature of his injuries.