It is believed two cars and a truck collided on Tonkin Highway near the intersection of Forrest Road about 6.15am on Tuesday.
UPDATE: A man has died in a crash south-east of Perth.
It is believed two cars and a truck collided on Tonkin Highway near the intersection of Forrest Road about 6.15am on Tuesday.
The male driver of one of the cars died at the scene, while the male driver of the second car was rushed to Armadale Hospital with serious injuries.
The driver of the truck was uninjured.
Major Crash investigators would like to speak to anyone who may have seen the crash.
Anyone with any information is asked to call Crime Stoppers on 1800 333 000 or make a report online at www.crimestopperswa.com.au
Tonkin Highway is closed southbound from Armadale Road to Rowley Road.
Motorists have been advised to seek an alternative route.
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