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.
Last call for donations to support Mandurah's homeless
State Government commits to building $5 million electrical training facility at Rockingham TAFE
McDonald's approved for Dawesville
Wanted man known to frequent Kwinana, Mandurah and Rockingham areas
Mandurah woman completes grueling English Channel swim
Man and child seriously injured in South West crash
Motorists warned to expect delays during Kwinana Freeway upgrades
Driver injured in Serpentine crash
Man and woman wanted for questioning over Lakelands car theft