Police are calling on friends or family of a man involved in car crash in Bunbury on Tuesday to come forward and identify him.
A white man in his late teens or early 20s has been flown to Royal Perth Hospital in a coma after his small off-road motor cycle collided with a car that was leaving a driveway on Timperley Road, South Bunbury.
The crash occurred about 6am and the rider received serious head injuries.
The rider has a slim build, weighs approximately 60kg, is about 170cm tall, has short ginger hair and a scruffy goatee beard.
The bike has blue guards, a black seat, blue wheel rims and appears to be new.
Police are calling for anyone who has a friend or loved one that fits the description who is missing in that area to call police on 131 444.
Please call Crime Stoppers on 1800 333 000 with any information about the crash.