Infamous US gangster James “Whitey” Bulger has been killed shortly after his transfer to a federal prison while serving life sentences for 11 murders.

Bulger, once one of America’s most wanted fugitives and the inspiration for movies such as Martin Scorsese’s The Departed and Black Mass starring Johnny Depp, was found dead at Hazelton high-security penitentiary in West Virginia, the federal Bureau of Prisons said Wednesday morning (AEST).

The 89-year-old was killed on the same day he was transferred from a Florida jail.

The cause of his death has not yet been released, but Richard Heldreth, a local union official for correctional workers at the prison, told CBS that Bulger’s death was the result of a homicide.

“This is the third homicide in seven months at our facility,” he said, adding that the prison was heavily understaffed and short of about 40 officers.

Bulger, who lead South Boston’s Winter Hill gang in the 1970s and ’80s, was captured by police in 2011 after being on the run for more than 16 years.

The model for Jack Nicholson’s ruthless crime boss in the 2006 Acadamy Award-winning movie The Departed, Bulger led a largely Irish organised crime gang that ran loan-sharking, gambling and drug rackets throughout Boston. He was also an FBI informant who informed on the rival New England mafia.

Bulger fled Boston in 1994 after being warned he was about to be arrested and became one of the FBI’s ‘Ten Most Wanted’ fugitives with a place just below Osama bin Laden.

In November 2013, a federal jury found Bulger guilty of murdering 11 people between 1973 and 1985, as well as 31 counts of racketeering, extortion, money laundering, drug dealing and weapons possession.

In handing down the sentence of two consecutive life terms and an additional five years, US federal Judge Denise Casper said to Bulger: “your conduct merits the most severe penalty.”

“The scope, the callousness, the depravity of your crimes, are almost unfathomable.

“Your crimes were all the more heinous because they were all about money,” she said after also ordering $19.5 million restitution for Bulger’s victims.

-with agencies