Former Chicago mob leader Joe ‘The Sledgehammer’ Andriacchi has died at the age of 91, according to the I-Team.

CHICAGO (WLS) — A longtime Chicago mob boss has died. According to I-Team sources, 91-year-old Joe Andriacchi died in his sleep over the weekend.

His pedigree dates back to the 1960s, when he was nicknamed “The Sledgehammer” for his not-so-delicate method of breaking open a safe.

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Andriacchi rose within the Chicago Outfit to become a thief and safecracker, but was apparently not talented enough to avoid prison for burglary in the late 1960s.

After he got out of prison, he climbed the criminal ladder, becoming a trusted boss who ran lucrative Rush Street gangs.

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Eventually, with the deaths of even more senior mobsters, including John “No Nose” Difronzo, Andriacchi assumed the number two position in the Outfit on several occasions, becoming the mob’s operational head honcho.

“There are generations rolling through here as far as the history of the organization,” said John Binder, a Chicago-based organized crime expert and author.

Binder said Andriacchi also earned the nickname “The Builder” in his later years because he owned a construction company.

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“By 1950, the IRS would no longer allow you to report, ‘Oh, I made $300,000 in miscellaneous income last year,’ they wouldn’t accept that,” Binder said. “You had to show a source of income. So all these guys like Accardo who were going around saying, ‘I had all this miscellaneous income,’ they all started to find some kind of, in many cases you might call it a cover-up.”

Federal investigators have long suspected Andriacchi of being involved in the disappearance of suburban mobster Anthony “Little Tony” Zizzo, who went to a meeting on Rush Street and was never seen again. The suspected motive may have been a feud with Mike “Fat Boy” Sarno.

“If somebody had set him up, somebody had arranged for him to have a little lunch with him… He left his house, his wife knew that, that morning to, I guess, meet somebody for lunch. And then his car was found and Tony Zizzo’s car was not,” Binder said.

The Outfit is an enterprise whose members are either related by blood, or by blood oath, or both. Andriacchi was related in both ways to one of Chicago’s most powerful and memorable mob bosses: Joseph “The Clown” Lombardo was Andriacchi’s cousin.

Lombardo was defeated in the great Family Secrets mafia murder trial and died in federal prison. Andriacchi was able to avoid prosecution.