Mafia boss Giuseppe Dainotti, 67, was shot in the head by two killers while cycling along a street in Palermo on Monday morning.
Witnesses called police after hearing gunshots at around 7:50 am in the street.
“My children had just left for school," a local woman said.
"I looked out and I saw a man on the ground losing blood from his head.
“There was no one else around, but soon afterwards a boy with a blue t-shirt came over, shouting 'uncle Peppino, uncle Peppino'.”
A boss of the Porta Nuova family, the high-profile gangster was released from prison in 2014 after serving a lengthy sentence for murder, drug trafficking and robbery.
Dainotti’s death is a strong reminder that Sicily’s Cosa Nostra mafia is still present, despite remaining relatively quiet in recent years.
“When people say the mafia is finished or has been defeated, sooner or later something happens that shows that the mafia is still here,” Palermo prosecutor Francesco Lo Voi said.
The shooting took place almost 25 years to the day since anti-mafia magistrate Giovanni Falcone was murdered in a bomb explosion.
Falcone, who was murdered on May 23, 1992, spent most of his career working tirelessly to combat organised crime in Sicily.