A show of "courage and strength" could trigger revenge attacks at any time after the slaying of gangland figure Sam "The Punisher" Abdulrahim.
As police discovered a second burnt-out car linked to the shooting, a crime expert warned retaliation by underworld hitmen was always on the cards.
Underworld killings tended to take a tit-for-tat-type pattern, Deakin University criminologist David Bright said.
"It may be that it simmers for a while and we might not see anything for a few weeks or months, or it may be that there will be immediate revenge and retribution," he told AAP.
Abdulrahim was walking with his girlfriend when the former Mongols bikie was gunned down in a Preston apartment block's underground car park in Melbourne on Tuesday.
The 32-year-old from Thomastown, who had survived at least half a dozen assassination attempts and recently returned to Melbourne from overseas, died at the scene.
A Porsche SUV was found burnt out about 4km away at Reservoir an hour later.
A grey Ford Ranger with a distinctive sticker of bull horns on the ute's canopy rear window was found at Westmeadows and was also set ablaze, police confirmed on Wednesday.
Both vehicles are thought to be linked to the shooting, with police calling for anyone who may have seen either car travelling through the area or with dash-cam footage to come forward.
Homicide Squad Detective Inspector Dean Thomas indicated investigators were working on the theory the ute was used as a second getaway vehicle.
"The offenders may have got into (it) after they'd burnt the Porsche," he told Melbourne radio station Nova.
Dr Bright said there were two sets of issues at play following Abdulrahim's death - the impact his killing would have on illicit businesses he was connected to and issues around loyalty and brotherhood, which could result in revenge.
There had been speculation that Abdulrahim had been involved in the illicit tobacco trade and his death might increase conflict between two competing groups, Dr Bright said.
"The only way to protect one's business and to compete is often through violence in order to gain the upper hand," he said.
But one thing Dr Bright is sure of is that the neither party will cower or retreat following the execution-style killing.
"The key qualities here are courage and strength," he said.
Det Insp Thomas said he was concerned about retaliatory attacks but reassured the community there was no suggestion of immediate threats.
Abdulrahim had survived multiple attempts on his life.
In May 2024, shots were fired at his Thomastown home, injuring the bikie-turned-boxer and in August the house was set alight.
He survived a shooting at Fawkner in June 2022 and was attacked with a rock in prison in 2018.
