An appeal has been made directly to the Greek "motherland" as the window closes to bring an alleged murderer to justice for a 25-year-old killing.
Father-of-two George Giannopolous was fatally stabbed when he intervened during a fight in a Sydney suburban nightclub on Anzac Day in 1999.
His sister on Tuesday made a public appeal in both English and Greek for information to help hold the 32-year-old's accused killer, James Dalamangas, accountable for the Belmore attack.
"It's been 25 years of battling through loss and grief with no justice or closure to help us through this pain," Toula Giannopolous said.
Police have never been able to trace Dalamangas - an underworld figure considered one of Australia's most-wanted men - after he reportedly fled to Greece shortly after a warrant was issued for his arrest.
After attempts to extradite him failed in 2003, Greek authorities agreed to begin their own prosecution over his alleged role in the killing.
That process was suspended in 2007 when he could not be located, but investigators believe he is still residing in the European country.
Ms Giannopolous said her brother was a loving husband and father, adding that the siblings' now-elderly parents had long suffered because of his death.
"I believe there's people both here and in Greece who are covering (Dalamangas) up and it makes it damn hard for my family," she said.
Ms Giannopolous called for the alleged murderer to turn himself in, saying justice would mean everything to her family.
NSW Police superintendent Grant Taylor said police believed there were people in Greece who knew where Dalamangas could be found.
"We want to emphasise that the family is Greek as well," he said.
"They're appealing to the hearts of the motherland."
Australian Federal Police superintendent Jared Taggart said his organisation had been working closely with Hellenic Police as the 25-year-long Greek statute of limitations neared its end in April.
Once the period was up, the prosecution of Dalamangas within Greece was unlikely.
"We will continue to do whatever we can to bring him back to Australia," Detective Superintendent Taylor said.
A $200,000 reward remains in place for information leading to Dalamangas's arrest and police released an image of what the 54-year-old may look like today.
Dalamangas's brother Peter died in 1998 after being held to the ground by up to seven security officers during an altercation at Sydney's Star City casino.
A magistrate described the now-fugitive as the "catalyst" for the brawl, in which he was also injured.
