Police are hoping for a breakthrough in a decades-old mystery that has left Homicide Squad detectives stumped.

Victoria Police has released a new image of a man whose body was found in mysterious circumstances in Roxburgh Park, in Melbourne's north 30 years ago.

The man was found lying in long grass in the North Point Busines Park, near the Cliffords Road side, on the morning of May 1, 1995.


The man had been severely beaten and suffered a number of stab wounds to his upper body.

He was found by two members of the public who then contacted police.

The man is described as 25-35 years of age, Caucasian, 179cm tall with a solid build and medium length brown hair, slightly receding.

Investigators said he had brown eyes and a scar under his right arm, and was found wearing a navy blue jumper, grey Nike T-shirt and shorts.


Mystery encounter at Sunbury may be linked

Police conducted a number of appeals for information in the 90s, which led to a report of a possible sighting of the man in Sunbury, 17 kilometres away, on the evening before he was found.

A person told police a man fitting the dead man's description had knocked on the door of a property in Sorbonne Drive, Sunbury about 6:40pm that evening.

The resident of the house closed the door and contacted police, but when they returned to the front door the man was gone.

The resident said the man had severe facial injuries and was bleeding from a head wound.

Despite an extensive police investigation, the man has never been identified and those responsible for his death have never been found.

Searches of his fingerprint and dental records have failed to find any match and police believe he has never been reported as missing.


Police still hope to solve 'genuine mystery'

Detective Inspector Dean Thomas from the Homicide Squad said police are hoping the new image of the man will provide them with a new avenue of enquiry.

"For the past 30 years, this man has only been known to us as 1238/95," he said.

"We also don't know how he came to be lying on that dirt road in Roxburgh Park and the circumstances that led up to his death."


Police previously released computer-generated images of the man in 1995 and 1999, but advances in technology have allowed them to produce what they say is the most accurate image yet.


"We are reasonably confident he is the same man that knocked on the door of the house in Sunbury, however the hours between then and him being found in Roxburgh Park remain a mystery," Inspector Thomas said.

"Our priority is to identify him and determine whether he has a family out there who have been searching for answers for the past three decades.”

A $50,000 reward for information which was issued in 2000 is still active.

Anyone with information is urged to contact CrimeStoppers on 1800 333 000.

Written by ABC News.