Police are seeking witnesses to an incident involving a firearm on Forrest Road, Armadale on February 6.
At about 9pm to 9.45pm a 21 year old woman driving a white BMW hatchback along Forrest Road noticed a burgundy Daewoo driving erratically behind her.
The vehicle tailgated her for a short distance and then overtook her.
A man then pointed his arm out of the vehicle and the victim believes she may have seen a firearm.
The car then drove away from the area.
The offending vehicle was found in Beeliar on February 8 after it evaded police and a firearm was recovered.
Police are asking anyone who may have witnessed the incident to contact Crime Stoppers on 1800 333 000 or make a report online at www.crimestopperswa.com.au.