The family of a man who died after mysteriously plunging into the Murray River near the Victoria-NSW border say they are in "constant pain" as the case remains unsolved nearly six years on.
Terrence McCallion, 55, was located fully clothed in the water by passers-by onboard a houseboat between Bruce's Bend and Psyche Pumps in Mildura about 3pm on May 1, 2015.
A man on the riverbank, who is a person of interest to police, yelled out to the people onboard the houseboat to help.
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https://twitter.com/VictoriaPolice/status/1379150091773214720He then allegedly left the scene in Mr McCallion's white Nissan Pulsar shortly after.
The passers-by used a small boat to recover the Buronga man, commencing CPR before emergency services arrived.
However, he died in hospital later that night.
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Police suspect McCallion may have been assaulted and have spoken to the man of interest on numerous occasions since the death.
Desperate for answers, the family said their anguish had not subsided, as they have been unable to find closure with mystery still looming over their father's death.
"The death of a parent is never easy but the violent nature of dad's death and the mystery surrounding it made it especially traumatic," Mr McCallion's children said.
"Dad welcomed everyone into his home and created an extended family that he loved as his own.
"We have been left wondering what happened to him and why.
"Answers will help give us much-needed closure, so we can finally move forward from the constant pain of not knowing, to remember him for who is was and what he meant to each of us."
Detectives are still working to piece together the circumstances which led to the man plunging into the river that afternoon and have appealed for people with any information to come forward.
"We haven't given up on solving the case and are hopeful someone in the community is now ready to come forward with information," Mildura Crime Investigation Unit Detective Acting Sergeant Adam Brymer said.
"Terrence's family have a right to know of the circumstances in which led him to his death so they can get the closure they deserve.
"No matter how small or insignificant the information may be, it could be all we need to piece together the case.
"If you know anything about Terrence's whereabouts in the lead up to his death, then now is the time for you to come forward and speak to us.'"
Investigators are hoping people in the community may have information about the victim's earlier movements on April 30 and the morning of May 1.
Police have also released images of his vehicle, which had a distinctive spider sticker on its back-right door, in the hope someone may have seen it prior to or following the incident.
Anyone with information about Mr McCallion's death is urged to contact Crime Stoppers on 1800 333 000.
