Matteo Messina Denaro (1962–2023) was the final boss of the Sicilian Mafia and one of Italy's most wanted fugitives for 30 years. Wanted for multiple murders including the kidnapping and murder of an 11-year-old boy, he finally surrendered to Italian authorities in January 2023 while receiving cancer treatment at a clinic in Palermo — hiding in plain sight under a false identity. He died of cancer in September 2023 while in custody.

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Matteo Messina Denaro on Wikipedia

https://en.wikipedia.org/wiki/Matteo_Messina_Denaro