Milan, May 7 - The son of a financial liquidator killed on the orders of a late Mafia-linked banker with ties to Giulio Andreotti on Tuesday walked out of a Milan commemoration of the seven-time premier who died Monday aged 94. Centre-left Lombardy co-ordinator Umberto Ambrosoli is the son of Giorgio Ambrosoli, a Milanese lawyer slain by the Mafia in 1979 at the age of 45 after he found evidence of malpractice while liquidating one of the Italian banks of Michele Sindona - a Cosa Nostra-linked Sicilian financier once hailed by Andreotti as "the saviour of the lira". Umberto Ambrosoli walked out of a regional assembly commemoration of former Christian Democrat statesman Andreotti, saying: "I have a personal history which mingles with the dark sides of Andreotti's. "It is right for institutions to commemorate men of institutions, but those belonging to them should examine their consciences". Lombardy Governor Roberto Maroni of the right-wing Northern League called Ambrosoli's act "inelegant". Giorgio Ambrosoli was named by a court as liquidator of Banca Privata Italiana, one of the biggest private Italian banks controlled by Sindona. After finding evidence of criminal malpractice he provided the US Justice Department with evidence to convict Sindona for his role in the collapse of the Franklin National Bank. According to Ambrosoli, Sindona paid an illicit $5.6 million commission to Vatican Bank chief Cardinal Paul Marcinkus, who later left his post under a cloud, and Roberto 'God's Banker' Calvi, the former head of Italy's biggest private bank, who was found hanging under Blackfriars Bridge in London in 1982, slain by Cosa Nostra, Italian prosecutors said, because he failed to pay them back huge sums of money. On July 11, 1979, a few hours after talking to US authorities, Ambrosoli was shot dead by three Mob hitmen commissioned by Sindona. Sindona was afraid Ambrosoli would expose his shady dealings in the Banca Privata Italiana case, Italian courts found. Shortly before Ambrosoli was killed, the American Mafia hitman William Arico, a convicted bank robber, made an apparently intimidating reference to Andreotti in a threatening phone call taped by the liquidator. Arico fell to his death while trying to escape from a federal prison in New York in 1984. In 1986 Sindona was sentenced to life imprisonment for having ordered the murder. A poisoned cup of coffee killed him shortly after his sentence began, amid speculation he was going to 'name names'. According to Mafia informant Francesco Marino Mannoia, Sindona laundered the proceeds of heroin trafficking for the Bontade-Spatola-Inzerillo-Gambino network. The mafiosi were determined to get their money back and would have played an important role in Sindona's attempt to save his banks. Ambrosoli was killed shortly after he had a talk with Palermo Police chief Boris Giuliano, who discovered cheques and other documents which indicated that Sindona had been recycling the proceeds from heroin sales by the Mafia through the Vatican Bank to his Amincor Bank in Switzerland. Only 10 days after the killing of Ambrosoli, Giuliano was shot and killed by the Mafia on July 21, 1979. Ambrosoli was posthumously awarded a medal for civic heroism and a film about him was made in 1995, entitled A Middle-Class Hero, directed by Michele Placido. Andreotti, Italy's most influential postwar politician, was convicted and later cleared of Mafia links 10 years ago but judges said he had ties to the Mob until 1980 which could not be punished because they dated too far back. He was also convicted, and later cleared, of ordering the murder of a muckraking journalist.