Greek police are investigating the shooting death of a 46-year-old Greek-Australian man who was gunned down in a seaside suburb of Athens.

An autopsy on the body of John Macris was to be carried out. Police were investigating whether his death was related to his potential involvement in the drug trade or in organized crime. Authorities say he had run-ins with police in the past, both in Australia and in Greece.

Macris was once the target of an alleged murder plot in Sydney. Australian police did not immediately comment Friday on any potential Australian criminal link to the shooting.

Macris, who was married to a model who appeared on a Greek reality TV show, was shot as he left his home in Voula in his car on Wednesday evening. Police say he apparently left his car to take cover but was shot four times with a 9 mm handgun and died at the scene.

Police were seeking camera footage for clues to the killing and were conducting ballistics tests on the bullet casings to determine whether the weapon had been used in other crimes.

Macris had been involved in Sydney's organized crime scene. In Athens, he appeared as a businessman and reportedly owned a security company.

A warrant for Macris's arrest had been issued in Australia's New South Wales state for failing to attend court for sentencing on a conviction for driving while his license was cancelled, a statement from the state government said. Police did not say when the warrant had been issued.

Media reports say Macris relocated to Greece to avoid the warrant.

The police media unit could not immediately comment on whether any potential Sydney link was being investigated in relation to the crime in Athens.

But police sources told Sydney's The Daily Telegraph newspaper that Macris's death was unlikely to have Sydney connections.

Macris had a feud with the family of high-profile Sydney nightclub owner John Ibrahim over a nightclub business partnership.

Two of Ibrahim's brothers, Fadi and Michael, were charged with conspiring to murder Macris in 2009.

Police alleged the brothers mistakenly believed Macris was behind the near-fatal shooting of Fadi in 2009. Fadi was shot five times as he sat in his Lamborghini outside his Sydney home. No one has ever been charged.

A jury in 2013 acquitted Michael and another man Rodney Atkinson of conspiracy to murder. Prosecutors later dropped the same charge against Fadi. The arrests were made before the alleged plot targeting Macris was executed.

Sydney criminal lawyer Brett Galloway described Macris in Sydney as a small-time drug dealer with aspirations to become a big-time gangster.

Galloway said he represented Macris in court about a dozen times, mostly on charges relating to modest quantities of illicit drugs.

"He was a nondescript sort of dude who wanted to be a gangster," Galloway said.

"He wasn't a big criminal. He wasn't well known like some of the hoods around town," he added.

Macris's life of crime did not appear to be a financial success, the lawyer said.

"I wouldn't call Johnnie a generous man with his money," Galloway said.

"If you want to be a gangster, someone takes your spot eventually. That's how it goes," Galloway added.