POLICE are calling for witnesses to a fatal crash in Margaret River on Sunday night.
A blue Toyota Corolla was being driven south along Bussell Highway when it collided head-on with a silver Mazda 3 near the Margaret River airport.
South West Acting Inspector Richard Moore said a witness who was driving behind the Corolla noticed the vehicle driving on the wrong side of the road for 1.5 kilometres in a 100 kilometre an hour zone.
"The witness flashed his headlights at the car to attract the driver's attention before he lost sight of the car," Inspector Moore said.
The 26-year-old French male driver of the Toyota Corolla from East Perth died in the crash and his 28-year-old Chinese female passenger was seriously injured and flown to Royal Perth Hospital.
"It appears that the two people in the Corolla were not wearing seat belts which would have made a big difference," Inspector Moore said.
The 33-year-old female driver and 33-year-old male passenger both from Margaret River in the Mazda were both seriously injured with the driver flown to Royal Perth Hospital.
Margaret River police will prepare a report for the coroner.
Anyone with information regarding this crash or who saw either of the vehicles involved prior to the crash is asked to call Crime Stoppers on 1800 333 000.