BRUCETON MILLS, W.Va. (CBS News/AP) – Notorious Boston gangster James “Whitey” Bulger – who was captured in Santa Monica seven years ago – died in a West Virginia prison Tuesday, shortly after being transferred there, the U.S. Department of Justice confirms.

Bulger, 89, had been one of the FBI’s most wanted fugitives for 16 years until his 2011 arrest in Santa Monica.

James “Whitey” Bulger. (CBS Boston)

Officials with the Federal Bureau of Prisons said Bulger had just been transferred on Monday to USP Hazelton, a high-security prison with an adjacent minimum security satellite camp in Bruceton Mills.

In a statement Tuesday afternoon, the prison would only say Bulger was “found unresponsive” at 8:20 a.m. Eastern time Tuesday, and that “life-saving measures were initiated immediately by responding staff.” He was pronounced dead by the local medical examiner.

Law enforcement sources tell CBS News that it appears he was severely beaten by one or more of his fellow inmates shortly after his arrival at a federal prison in West Virginia on Monday.

“The Federal Bureau of Investigation was notified and an investigation has been initiated. No staff or other inmates were injured, and at no time was the public in danger,” the statement read.

Authorities did not immediately release a cause of death. Richard Heldreth, president of Local 420 of the American Federation of Government Employees, which represents workers at USP Hazelton, told CBS affiliate WPRI there was a homicide overnight, but he wasn’t told who was killed.

“This is the third homicide in seven months at our facility,” Richard Heldreth told the station. “We are very understaffed, we are short about 40 officers.”

Bulger had recently been moved from a prison in Florida to a transfer facility in Oklahoma City.

Bureau of Prisons officials and his attorney declined last week to comment on why he was being moved.

Bulger had been serving a life sentence after being convicted in 2013 in a sweeping racketeering indictment, which included counts of participating in 11 murders.

Bulger, the model for Jack Nicholson’s ruthless crime boss in the 2006 Martin Scorsese movie, “The Departed,” led a largely Irish mob that ran loan-sharking, gambling and drug rackets in the Boston area. He also was an FBI informant who ratted on the New England mob, his gang’s main rival, in an era when bringing down the Mafia was a top national priority for the FBI.

Bulger fled Boston in late 1994 after his FBI handler, John Connolly Jr., warned him he was about to be indicted. With a $2 million reward on his head, Bulger became one of the FBI’s “Ten Most Wanted” criminals, with a place just below Osama bin Laden.

When the extent of his crimes and the FBI’s role in overlooking them became public in the late 1990s, Bulger became a source of embarrassment for the FBI. During the years he was a fugitive, the FBI battled a public perception that it had not tried very hard to find him.

On June 22, 2011, a then 81-year-old Bulger and his then 60-year-old longtime girlfriend, Catherine Greig, were captured in Santa Monica where they had been living in a rent-controlled apartment near the beach at the Princess Eugenie apartment complex, located at 1012 3rd St., following a tip from the FBI’s Boston bureau.

Bulger, nicknamed “Whitey” for his bright platinum hair, grew up in a gritty South Boston housing project and became known as one of the most ruthless gangsters in Boston. His younger brother, William Bulger, became one of the most powerful politicians in Massachusetts, leading the state Senate for 17 years.

In working-class “Southie,” Jim Bulger was known for helping old ladies across the street and giving turkey dinners to his neighbors at Thanksgiving. He had a kind of Robin Hood-like image among some locals, but authorities said he would put a bullet in the brain of anyone who he even suspected of double-crossing him.

“You could go back in the annals of criminal history and you’d be hard-pressed to find anyone as diabolical as Bulger,” said Tom Duffy, a retired state police major who investigated Bulger.

“Killing people was his first option. They don’t get any colder than him,” Duffy said after Bulger was finally captured in June 2011.

Patricia Donahue, the wife of 1982 Bulger murder victim Michael Donahue, told CBS Boston the news of Bulger’s death brought closure for her and her family.

“We’re very happy that the man is not here any longer, because we don’t have to hear his name ever again,” Donahue said. “Myself, I’d like to open up a champagne bottle and celebrate.”

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