Pinjarra Police are seeking the public�s assistance into an incident that occurred at a petrol station on South Western Highway in Coolup on Wednesday, July 1.
About 3.40pm, the owner of the petrol station became aware of a disturbance on the forecourt at the front of the roadhouse.
He approached a white Mitsubishi Lancer, where a man exited the vehicle and punched him in the face.
While he was on the ground, other occupants exited the car and hit the owner.
A bystander who was refuelling his car nearby tried to assist the owner, but was hit to the side of the head.
Two female staff members, who came out to help, received minor injuries from two of the females in the vehicle.
The occupants of the Lancer left the petrol station, driving north on the South Western Highway towards the Pinjarra town site.
The petrol station owner and bystander attended Peel Health Campus for treatment.
The driver of the Lancer is a man, described as 30 to 40 years of age and dark skinned.
The second person sought is a man about 20 years of age, dark skinned and wearing a red t-shirt.
The third is a man approximately 20 years of age, dark skinned and wearing a black t-shirt.
The fourth is a woman, who is approximately 20 years of age, dark skinned and wearing a white top.
The fifth is a woman, approximately 20 years of age, dark skinned and wearing a grey top.
Anyone who saw the incident or has information is asked to call Crime Stoppers on 1800 333 000.