James "Whitey" Bulger, the notorious Boston gangster who eluded authorities for nearly two decades before being caught in 2011, was found dead in prison Tuesday, officials said.

His death is being investigated as a homicide, said Justin Tarovisky, executive vice president of the American Federation of Government Employees Local 420, which represents corrections officers at the West Virginia prison where Bulger had recently been moved.

Bulger, 89, was serving a life sentence after being convicted in 2013 of participating in 11 murders. He served as an FBI informant who ratted on his gang's main rival before becoming the agency's most wanted fugitives for 16 years until his arrest in Santa Monica, California.

A look at other notorious criminals who met a violent death behind bars:


Serial killer Jeffrey Dahmer was serving life prison sentences when a fellow inmate beat him with a metal bar while he was cleaning a prison locker room in 1994. The chocolate factory worker was arrested in 1991 and admitted killing 17 young men, most in Milwaukee, some of whom he mutilated and cannibalized. Dahmer's killer, Christopher Scarver, was already serving a life sentence for a 1990 murder when he bludgeoned to death Dahmer and another inmate of the Columbia Correctional Institution in Wisconsin.


John Geoghan was beaten and strangled to death at Massachusetts' maximum-security Souza-Baranowski Correctional Center in 2003 by a fellow inmate. Geoghan, who had accused of molesting as many as 150 boys over three decades, was serving a 9- to 10-year sentence for groping a boy and was at the center of the Boston clergy abuse scandal. His killer, 37-year-old Joseph Druce, planned the killing for a month, stretching out the socks used to choke Geoghan and doctoring a book to jam the cell door shut, authorities said.


Albert DeSalvo, who confessed — then recanted — to being the "Boston Strangler", was stabbed to death in 1973 at a maximum-security prison in Walpole, Massachusetts. DeSalvo was never indicted in the killings that terrorized the region and grabbed national headlines in the early 1960s, but was convicted in January 1967 of armed robbery, assault and sex offenses, and sentenced to life in prison. In 2013, DNA tests confirmed that DeSalvo did kill the woman believed to be the serial killer's last victim and then-Massachusetts Attorney General Martha Coakley said it was "most likely" that he was the Boston Strangler.


Donald Harvey, a former nurse's aide and serial killer known as the "Angel of Death", was fatally beaten last year by a fellow inmate in a protective custody unit at the state prison in Toledo. Harvey was serving multiple life sentences after pleading guilty in 1987 to killing more than three dozen hospital patients in Ohio and Kentucky during the 1970s and '80s. He later said he was responsible for killing 18 others while working at the Veterans Administration Medical Center in Cincinnati.


Richard Loeb and Nathan Leopold created a nationwide sensation in 1924 when they were convicted of kidnapping and slaying a young neighbor in Chicago just for the thrill of it. Loeb and Leopold, then 18 and 19 respectively, were sentenced to life terms for the murder plus 99 years for the kidnapping. Loeb was killed in a prison fight in 1936.