Armadale detectives are seeking witnesses to an incident on Thursday.
At around 5.30pm, a 36-year-old man exited his vehicle at the intersection of Burslem Drive and Spencer Road in Thornlie, to confront a driver of a grey Toyota Corolla about his erratic driving.
The driver of the Corolla also got out of his car before a physical altercation ensued.
As a result, the 36-year-old suffered a stab wound to his chest.
He was taken to Armadale Hospital where he remains in a stable condition.
The driver of the Corolla is believed to have fled the scene, travelling north on Spender Road.
Anyone who may have witnessed the incident, or has dashcam footage in the vicinity of the location between 5.15pm and 5.50pm is asked to contact Crime Stoppers on 1800 333 000 or make a report online at www.crimestopperwa.com.au.
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