A 41-year-old man was airlifted to Royal Perth Hospital after crashing his car earlier this morning.
The man's four-wheel drive towing a trailer collided with a tree along South West Highway near Keysbrook just after 1:30am.
Emergency services needed to use the jaws of life to cut the man from the wreckage.
The RAC Rescue helicopter airlifted the man to Royal Perth Hospital around 3am.
Fairfax reports a St John Ambulance spokeswoman said the man sustained possible leg injuries.
It's understood the man remains in a serious but stable condition.
Scorching Christmas temperatures for Perth, Rockingham, Mandurah
Teen charged over Baldivis arson attack
Concerns for missing boy last seen in Warnbro
Baldivis Sports Complex officially complete with unveiling of final stage
Teen dies at Logue Brook Dam
Mandurah named WA’s Most Accessible Community
Police attend separate crashes in Lakelands and Port Kennedy
Fresh new look for Roger May Machinery Museum
Tragic end to search of missing FIFO worker