Ex-mob hit man 'Mad Dog' Sullivan dies in NY state prison

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Authorities say Joseph "Mad Dog" Sullivan, a former organized crime hit man suspected of carrying out more than 20 killings, has died in a New York prison.

Prison officials say Friday that the 78-year-old New York City native died June 9 at Fishkill Correctional Facility in the Hudson Valley. A medical examiner says his death was from natural causes, but a specific cause hasn't been determined.

Sullivan was serving 87 years to life in prison after being convicted of three murders, including the shooting of a Teamsters leader outside a suburban Rochester restaurant in 1981.

Sullivan was the only inmate to escape from Attica, a maximum-security prison. In 1971, he buried himself beneath a pile of empty flour bags in the back of a truck leaving the prison. Caught in Manhattan, he was paroled in 1975.