A man in his 60s is being treated for serious injuries after a crash between a car and truck sparked a major emergency response north of Perth.
Emergency crews were called to Great Northern Highway in Chittering just after 7am on Thursday, where two people were cut free from a vehicle.
Three St John Ambulance units responded under priority one conditions, with police and DFES also called to the scene.
A man in his 60s was seriously injured and 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.
Great Northern Hwy remains partially shut at Chittering Roadhouse, with Main Roads alerting motorists to the crash and the reduced visibility.
The authority has urged drivers to avoid the area.
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