A dirt bike landed on top of a Pilbara teenager yesterday after a collision near Karratha.
A police spokesman said the 15-year-old boy was being treated for serious injuries in Royal Perth Hospital this morning the off-road crash about 6pm.
The boy was riding his bike on a dirt track near the intersection of Balmoral and Cossack Road when he collided with a 28-year-old man who was also riding an off-road motorbike in the opposite direction.
It is believed that the pair collided at a blind spot on the track and both riders were thrown from their bikes.
The teenager was taken to Nickol Bay Hospital before being airlifted to Perth by the Royal Flying Doctor Service.
In another serious crash yesterday, a teenager was injured when he lost control of his car in Upper Swan and hit a kerb.
Police said the 17-year-old's vehicle struck a power pole and rolled down and embankment on Great Northern Highway near Orchard Road about 3pm.
The driver was trapped and the Department of Fire and Emergency Services cut him free before the RAC Rescue Helicopter took him to hospital.
The rescue chopper was also deployed to a motorcycle crash in Halls Head this morning.
A 34-year-old man was riding his motorcycle on Marty Street about 12.20am when he failed to negotiate a bend and hit a Give Way sign.
The man was taken to Royal Perth Hospital with serious facial injuries.
Earlier last night a 44-year-old man and a six-year-old boy were injured in a crash in Scarborough.
About 6.25pm the car was pulling out of a car park on Scarborough Beach Road when two vehicles stopped to let the vehicle enter the road.
The motorcyclist rode between the two stationary vehicles before striking the side of the moving car.
The 44-year-old, of Bibra Lake, was thrown from the bike and received serious injuries which he is being treated for at Sir Charles Gairdner Hospital.
The boy, who was a passenger in the vehicle, received minor injuries and was taken to Princess Margaret Hospital.
Anyone with information regarding any of these incidents is asked to call Crime Stoppers on 1800 333 000.