Convicted Chicago mobster Frank Calabrese Sr. has died in prison at 75.
US officials said he died on Christmas Day at the Butner Federal Medical Center in North Carolina, without releasing his cause of death, reported BBC News. Calabrese — who had claimed he had numerous ailments, including an enlarged heart — was serving a life sentence after a a 2007 conviction. His trial involved 18 decades-old murders.
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"It's very emotional right now because there were two sides to my dad, and I miss the good side," Calabrese's son, Frank Jr., told the Chicago Sun-Times. "It's always been hard for me that he had to be locked up like that. Then again, I didn't forget a lot of the things that happened."
Calabrese was known for the terror he wreaked on the streets as well as the violence he inflicted on his own family, according to the Sun-Times. His former defense attorney, Joseph "The Shark" Lopez, said his December 25 death was ironic, since his favorite holiday was Christmas.
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The mobster was among five men convicted in September 2007 at the Family Secrets trial, according to the Associated Press. The trial resulted from a multi-year effort by the federal government to take down the Chicago Outfit, the name the organized crime family gave itself.
The Chicago Tribune noted that a federal jury held Calabrese and two other mobsters — Joseph "Joey the Clown" Lombardo and James Marcello — responsible for 10 murders.