A major emergency response in underway north of Perth after a crash between a car and truck.
Emergency crews were called to Great Northern Highway in Chittering just after 7am on Thursday.
Two people were cut free from a vehicle and a man in his 60s has been seriously injured.
Three St John Ambulance units responded under priority one conditions and remain on the scene.
The man has been rushed to Royal Perth Hospital under lights and sirens.
Heavy fog was especially bad across Perth on Thursday morning, in particular to the north and east.
Main Roads has partially shut down Great Northern Hwy at Chittering Roadhouse, alerting motorists to the crash and the reduced visibility.
It urged drivers to avoid the area.
More to come.
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