Officers from the Major Crash Investigation Section continue to investigate a fatal crash which occurred in Karnup yesterday morning.
Around 9:15am, a member of the public discovered a male in bushland off the Kwinana Freeway just south of Paganoni Road.
Police believe the man was travelling on a Yahama motorcycle in the southbound lane of the freeway when he left the road and crashed.
The 29-year-old man received fatal injuries and was pronounced dead at the scene.
At this stage it is unknown when the crash occurred.
Anyone with information is asked to contact CrimeStoppers on 1800 333 000 or report online via crimestopperswa.com.au
Dashcam or mobile phone footage can be uploaded to the link below: