A Sydney man believed kidnapped had pleaded not to be extradited from the United States over a murder because a crime family had put a $100,000 bounty on his head.
Six years later, Raphael Joseph climbed into a car with at least two other men in Sydney's west in the early hours of March 21 and hasn't been seen since.
NSW's homicide squad believe an extortion attempt may be behind Mr Joseph's disappearance.
Mr Joseph, 38, was extradited from the US to Australia over his suspected involvement in the fatal shooting of Dimitri Debaz in the car park of the Playhouse Hotel in Sefton in 2002.
Mr Joseph, known as Huss or Hussany to his mates and family, fled to the US and was arrested in 2006 after a four year search.
In 2008, he pleaded with then US Secretary of State Condoleezza Rice to keep him in the country, claiming he would be tortured or killed by a rival gang in Australia.
His plea failed and he appeared in court in Sydney in July, 2008, charged with murder, but the case was later dropped.
It is understood he was affiliated with the Assyrian gang Dlasthr - The Last Hour.
He claimed an Australian crime family had a $100,000 bounty on his head payable to anyone who killed him, and members of Sydney's Bronx Boys gang wanted to murder him.
His lawyer filed documents at the time alleging Mr Joseph's friends and associates had been kidnapped and tortured.
NSW police believe Mr Joseph himself has now been kidnapped.
Detective Superintendent Mick Willing said extortion was a potential motive.
Mr Joseph's family was due to hold a media conference with police, but pulled out at the last minute because they were scared and distressed.
Mr Joseph lived in the inner-west, waterfront suburb of Chiswick.
On March 20, hours before he went missing, he spent time at the Star Casino and may have also met someone at a McDonald's in Auburn.
He was last seen getting into a silver sedan on Dartbrook Road at Auburn late on Thursday, March 20, or early the next morning.
His family reported him missing on March 22.
Police have found Mr Joseph's white Mercedes car, which he drove to Auburn.
Det Supt Mick Willing said police believe a number of people knew where Mr Joseph was.
"His poor family are worried sick and are desperate to know what has happened to him," he told reporters on Thursday.
Police scoured bushland and private properties in the Flemington area last week for evidence.
Anyone with information can contact Crime Stopper anonymously on 1800 333 000.
