Police are appealing for public assistance as they try to determine how a 23 year old man was injured in Mount Lawley.
He was found with serious injuries in the car park of a shopping centre on Walcott Street just before 7am yesterday.
It's believed he may have been hit by a white delivery truck.
That truck has been seized by Police and will be forensically examined.
Anyone with information should call Crime Stoppers on 1800 333 000 or visit www.crimestopperswa.com.au.