A map showing the getaway path of an alleged killer has has been released by police investigating a Melbourne shooting murder with criminal underworld connections.
Daniel O'Shea, 41, was found dead by joggers in South Yarra's Fawkner Park on April 26, with two guns found nearby by children the next day.
The victim - who had criminal connections in Australia and abroad - is believed to have been in the park for a pre-arranged meeting and detectives have sourced footage of a man leaving the area on the night of Mr O'Shea's death.
"This is a particularly horrendous murder," Detective Inspector Andrew Stamper told reporters on Thursday.
"It's no secret that Mr O'Shea was involved in criminal activities. We know that and he was well connected in that criminal community both nationally and internationally.
"Obviously it presents us with some challenges due to the criminal code of silence."
An image has been released of a man wanted over the shooting, and shows him wearing black clothes and a green baseball cap, and carrying a red and white Coles plastic shopping bag.
"This person may be a member of the community who was innocently walking through the park. If that's the case and you do recognise yourself, get in touch with us straight away. That's no issue," Insp Stamper said.
"But at this stage we obviously have reason to believe this person is a significant person of interest."
The shooting is believed to have been targeted and police have not ruled out the possibility of an ambush.
They earlier stressed there was no ongoing threat to the community after Mr O'Shea's killing.
"He's still somebody's son, somebody's partner, somebody's friend. There's people grieving out there regardless of his background," Insp Stamper said.
He was shot on the western side of Fawkner Park closest to St Kilda Rd and CCTV showed the suspect walking in the opposite direction and crossing over Punt Road into Toorak Road, which he walked along for 2.5kms with a phone in his hand.
"It wouldn't look unusual in Toorak Road ... but I'm thinking somebody who knows this guy would see those images and would be able to identify him," Insp Stamper said.
People with information should contact Crime Stoppers on 1800 333 000.