Mafia turncoat who revealed secrets of Cosa Nostra has been freed from Rome prison.

There was anger and disbelief in Italy last night at the news that one of the Sicilian Cosa Nostra's most infamous killers has walked free after serving 25 years in jail.

The release of former Mafia boss Giovanni Brusca, who turned state's evidence after his 1996 arrest, has provoked outrage among the public, politicians and the relatives of his victims.

Brusca, who once stated that he had committed or ordered more than 150 murders, is most notorious for the 1992 Capaci bombing in which five people were killed including anti-mafia magistrate Giovanni Falcone.

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In 1996 Brusca ordered the strangling of a 14 year-old boy, son of a fellow-mobster who had turned informer, after holding him hostage for 779 days.

The boy's body was then dissolved in a barrel of acid, in a horrific act of revenge against his father, Santino Di Matteo.

A ruthless killer known as 'U verru (Sicilian dialect for "The Pig"), Brusca was arrested in 1996, five months after the murder of young Giuseppe Di Matteo.

He had already been sentenced to life in prison in absentia for Mafia association and multiple murders, and following his arrest he turned 'pentito' and began to collaborate with prosecutors.

His release last night was condemned by Tina Montinaro, the widow of Falcone's police escort officer Antonio Montinaro who was blown up in the Capaci bombing.

"I am outraged, I am truly outraged. The state is rowing against us" - she told Italian news agency Adnkronos - "The whole of Italy should be outraged."

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Maria Falcone, sister of the slain judge, said of the news: "From a human point of view it pains me, but this is the law, a law that my brother himself wanted and therefore it should be respected."

Politicians also expressed their outrage after Brusca walked out of Rome's Rebibbia jail yesterday evening, 45 days before the conclusion of his sentence.

Matteo Salvini, leader of the right-wing Lega party, said: "This is not the justice that Italians deserve," while Rome mayor Virginia Raggi described Brusca's release as "an unacceptable disgrace, an injustice for the whole country."