The southbound lanes of Kwinana Freeway have been shut and trains have been halted after a truck rolled and slammed through a barrier.
The lanes between Rowley and Anketell roads were closed by emergency services as St John WA paramedics and police responded to the crash about 8.50am.
Police said the truck rolled 300m south of Rowley Road before slamming through a freeway barrier, leaving the vehicle close to the train tracks, in Wandi
It is believed the driver of the truck has been critically injured.
Transperth issued a statement about 9.45am announcing that trains on the Mandurah Line between Cockburn Central and Rockingham were closed. Replacement buses are running instead.
Motorists were initially out of their vehicles at the scene before the route was closed, with debris understood to have been scattered across several lanes.
