Italian mafia boss Provenzano died from a heart attack in a Milan hospital aged 83, prison authorities said on Wednesday.
Provenzano, dubbed "The Tractor" for his ruthless trait of mowing people down, was arrested and jailed in 2006 after spending 43 years on the run.
Bernardo Provenzano was a member of the Sicilian Mafia (Cosa Nostra) and was suspected of having been the head of the Corleonesi, a Mafia faction that originated in the town of Corleone and de facto capo di tutti capi (boss of bosses) of the entire Sicilian Mafia until his arrest in 2006.
He was said to have taken over command of the Sicilian Mafia after the 1993 arrest of ex-boss Salvatore "Toto" Riina.
He successfully evaded capture for decades partly due to his refusal to embrace modern, traceable communication methods. From his last hideaway, a rundown farmhouse in the Sicilian countryside, he gave orders and kept in touch with contacts using only written messages – known as 'pizzini' –which were hand delivered by trusted henchmen.
Provenzano was serving a life term for several murders, including the killing of two judges in 1992.
Provenzano has spent the last couple of years in solitary confinement in a prison hospital. Earlier in april judges denied a request to relax the strict prison regime because of the boss's frail health, arguing that he still has the ability to run his criminal organization.