Police chase down man after alleged assault

A Collie man who allegedly threatened an elderly man with a broken bottle as he tried to steal his car has been arrested by police.

Police say a 79-year-old man was parked outside a store at Pratt Road in Eaton about midday today when an unknown man allegedly approached the car.

Police allege a struggle occurred after the man allegedly tried to steal the car and threatened the elderly man with a smashed bottle.

A number of people were able to wave down a police car in the area at the time of the alleged offence and after a short foot chase a man was arrested.

The elderly victim received a minor injury to his hand.

The 30-year-old Collie man has been charged with one count of armed robbery and is due to appear in Bunbury Magistrates Court tomorrow.