Mafia supergrass lifts the lid on a trail of blood from Sicily to Milan

The crime stories of the most notorious Sicilian mafiosi of recent years are being rewritten this week in Milan as the result of the testimony of a new and, as yet, unidentified supergrass.

A former gangster, from the southern Sicilian city of Gela, is explaining to Milanese prosecutors exactly how, when and why the Sicilians extended their reach to Milan, at the opposite end of the Italian peninsula.

Prosecutors believe the turncoat, who extorted and killed alongside the top mafiosi of the day, may help them to solve 10 or more murders committed in Italy's biggest city in the 1980s and early 1990s. And yesterday the chief prosecutor involved in the case, Marcello Musso, said the evidence his team was obtaining could also shed light on the hidden activities of Gela-based mobsters in the city today, some of whom, he said, are still "militarily active and dangerous".

Milan, Italy's commercial capital, clung onto its reputation as an enclave of capitalistic probity and rectitude until the explosion of the so-called "Tangentopoli", or "Bribesville" corruption case in the early 1990s which exposed the seedily symbiotic relationships between the city's politicians and businessmen who funded them.

But if the latest Mafia informer is to be believed, Sicilian gangsters were deeply involved in the city many years before.

The most notorious of those whose names have come up this week is Toto Riina, the 5ft 2in former capo di capi known familiarly as Toto u curtu ("Shorty") or la Belva ("the Monster").

Riina, aged 76, the boss said to have killed 40 people and to be responsible for the deaths of 1,000 more, including investigators Giovanni Falcone and Paolo Borsellino, was - by coincidence - rushed from prison to hospital in Milan last week, suffering from heart problems. Though based throughout his career - much of it on the run - in Sicily, Riina is quoted by the new supergrass as having boasted, "Milan is in our hands."

The investigators believe many of the unsolved killings followed a fixed pattern, reflecting the tight command structure of the Mafia. Riina or his then second in command Bernardo "the Tractor" Provenzano, issued orders for the murder of rivals or traitors to the Corleone clan active in Milan.

The orders went down the line to a lieutenant, a gangster from the Gela region called Giuseppe Madonia, who activated hit-men from Gela based in Milan. The objective was to secure unrivalled control of this lucrative domain.

The convicted and imprisoned gangsters who have been interrogated constitute a roll-call of the most feared men in Italy of recent decades: not only Riina and Provenzano but also Luca Bagarella, Antonino Giuffre (a lieutenant of Provenzano, turned informer in 2002) and Giovanni Brusca. Brusca, nicknamed Il Porco, "the Pig", for his seedy appearance, admits to 100 murders including the detonation of the bomb that killed Giovanni Falcone, his wife and three others, and the strangling of 11-year old Giuseppe di Matteo, the son of a Mafia informer whom Brusca held in captivity for 18 months before killing him and dissolving his body in acid.

During the long months that little Di Matteo was being tormented and tortured by Brusca, one of the men guarding the boy was another gangster from Gela: Daniele Emmanuello, now 33, a fugitive from justice for 10 years, accused of murder, drug-trafficking and other Mafia crimes.

Investigators hope their new informer may bring new clues as to the whereabouts of Emmanuello.