A three-year-old boy has escaped unhurt after a gunman opened fire on his mother's car near Dwellingup.
Police say the shooting was the first of two separate firearms incidents on Friday.
In the second a man was arrested after opening fire at a house in Geraldton.
Narrogin detectives say the first incident happened around 11.40am as a women was driving her Mitsubishi Pajero along the Pinjarra-Williams road between Dwellingup and Boddington.
She told police that she saw a man in the bush on the side of the road and as she drove past he opened fire on her car.
The bullet went through the rear passenger door close to where her three-year-old son was sitting. He was not hurt.
She reported to shooting to police in Boddington. Officers from Boddington, Pinjarra, Waroona and Narrogin rushed to the scene but the gunman could not be found.
He is described as being between 30-40 years of age, 185cm tall, slim with tanned skin and short blond-brown hair. He was wearing black jeans and a long sleeved black shirt.
Meanwhile Geraldton detectives have charged a man after he opened fire at a house in Spalding, in the north of the city, late on Friday night.
They say the man and the people inside the house knew each other.
After he opened fire the man left the scene in a car with two other men.
The Hyundai was stopped by Geraldton police on Brand Highway a short time later and three men were arrested.
A 28-year-old man has been charged with a string of offences including threatening to kill, unlawfully discharging a firearm and unlawful possession of a firearm.
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