Police have issued pictures of a vehicle similar to that being driven in Swanbourne around the time of David Liam Johnson's death on March 8 in the hope it might spark information about his killer.
A police spokeswoman said detectives from the Major Crime Squad sought further help from the public with their investigation into the murder of the 32-year-old man, known to friends as Liam.
A post-mortem examination revealed evidence indicating that Mr Johnson had been struck by a vehicle before he was shot.
"Forensic evidence indicates that this occurred at another location before Mr Johnson was taken to Lime Kiln Field where he was subsequently shot and killed," a police spokeswoman said.
"Detectives are interested in identifying a dark-coloured station wagon which they believe might have been involved."
A vehicle similar in appearance to the two pictured below was believed to be driving in the Swanbourne area between 11pm and 11.30pm during the evening of Friday 8 March, 2013.
Mr Johnson's family is in disbelief over the murder, saying Mr Johnson was remembered for his friendliness.
Mr Johnson’s sister Ele and aunty Jennifer, who did not what their surnames published, have described Mr Johnson’s as “a free spirit” with no known enemies, who was known in the Mandurah and Fremantle areas.
“He would never hurt anybody, he was very kind hearted and with that gorgeous big smile he had you could not help but like him. He was friendly and chatty,” Jennifer said.
Detectives would like to hear from anyone who might be able to assist in identifying the vehicle.
Anyone with information is urged to contact Crime Stoppers on 1800 333 000 - callers may remain anonymous.