Mandurah Detectives are investigating a bizarre incident in which men impersonating police officers tricked and assaulted a 32-year-old man in Pinjarra on Monday night.
About 10.30pm the man was driving his 1981 Ford Fairlane along South Western Highway when he noticed a car travelling behind him.
The man assumed it was a police car and pulled over, after he noticed flashing red and blue lights behind him.
Two men got out of the car and approached the man’s driver-side window.
The men ordered the 32-year-old to get out of the car, before they assaulted him.
The man managed to break free from the two and then drove off in his car.
Detectives have described the car as a Ford Falcon that looked like an unmarked police vehicle.
One man was described as being tanned, with possible facial hair, of a solid build and around 185 centimetres.
Police said the man was wearing a shirt that either white or blue, and trousers that were possibly black or blue.
During the incident, the man received lacerations and bruising.
Anyone with information is asked to call Crime Stoppers on 1800 333 000 or make a report online at www.crimestopperswa.com.au.