A man who claimed to have witnessed the murder of anti-drugs campaigner Donald Mackay has contacted police, prompting detectives to revisit the longstanding mystery.
But there haven't been any major new developments in the 1977 case so far.
"Detectives were recently contacted by a man who claimed to have new information concerning Mr Mackay's death," NSW police said on Tuesday.
"This information was followed up, however it has not resulted in any significant development."
Mr Mackay is believed to have been murdered in his home town of Griffith for telling police the whereabouts of marijuana farms owned by Australian-born mafia.
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A coronial inquest found he died of gunshot wounds, but the body of the father of four has never been found.
Police and homicide detectives began revisiting the case following the latest claims.
The man claimed to have witnessed Mr Mackay being set upon by a number of people in a hotel car park, News Corp Australia reported.
He reportedly later fled Australia because he feared for his own life.
KEY DEVELOPMENTS IN THE DONALD MACKAY MURDER MYSTERY
*1977 - Donald Mackay is killed at Griffith in southwest NSW on July 15, in a suspected Italian-Australian mafia assassination.
*1979 - Woodward Royal Commission finds Mr Mackay was murdered by a Griffith-based cell of the Calabrian`Ndrangheta mafia and that Robert Trimbole, now dead, was one of its influential members.
*1986 - James Frederick Bazley is jailed for life for the murder of drug couriers and given nine years' jail for conspiring to murder Mr Mackay. He was released in 2001.
*2012 - A $200,000 reward is offered for information leading to the remains of Mr Mackay.
*2013 - Police excavate farmland in the NSW Riverina region in June amid speculation Mr Mackay's body may have been dumped in a well. The search fails to come up with anything.
