Major Crash Investigators are seeking information regarding a fatal crash in Birchmont last month.
Around 7.20am on Friday October 27, a blue Mazda sedan and a Kenworth truck were involved in a collision while driving south on Forrest Highway.
The 68-year-old female driver of the Mazda and her 69-year-old male passenger were taken to Royal Perth Hospital.
The female driver died on Thursday, November 9.
The driver of the truck wasn't injured.
Police urge anyone who saw the crash, has dash cam footage, or saw the vehicles involved travelling in the area prior to the crash, to contact Crime Stoppers on 1800 333 000.