The blast, heard for miles, blew out windows in apartment buildings and a school, destroyed the judge's armoured car and two police vehicles and showered passers-by with shards of glass and metal.
Mr Borsellino, 54, a walking databank on the Mafia, was left the nation's leading Mafia investigator after his close friend and collaborator, Judge Giovanni Falcone, the national anti-Mafia hero, was killed on 23 May in a spectacular bombing on a highway outside Palermo. Mr Falcone's wife and three police escorts were also killed.
'Two days ago I told (Borsellino) to leave Palermo,' said Pino Arlacchi, a sociologist who has studied the Mafia for years and knew both magistrates well. 'We're looking at a very clear strategy by the Mafia to kill,
one by one, inexorably, all those who have understood and accumulated knowledge about the Mafia.'
Referring to suspicions that Colombian drug traffickers had had a role in Falcone's assassination, Mr Arlacchi said: 'Let's not talk about Colombian connections . . . We have an enemy who is perfectly known.' Together, the two attacks wiped out a significant chunk of the state's front line against organised crime. The two men were considered brilliant and meticulous investigators of international organised crime and were the force behind convictions of hundreds of mob figures in the 1980s.
Giuseppe Ayala, an MP and former anti-Mafia investigator in Palermo, said that he heard an 'incredible blast' and raced out to his balcony, about 40 yards away. 'There were pieces of bodies all over . . . flames . . . The building and the one across from it looked like they were hit by a war.' Fragments of the car were sent flying up to 50 yards away.
The Mafia, Mr Ayala, said, are 'affirming their power' against the state. 'They're saying, 'We hit who we want, when we want.' '
'We are at war. It's a war with no limits and we must prepare ourselves to resist. We cannot dupe ourselves into believing this is the end,' said Aldo Rizzo, the Mayor of Palermo.
Claudio Martelli, the Justice Minister, called for an urgent session of parliament to enact a set of decrees, passed by the cabinet shortly after Falcone's killing, that toughens the way police and courts handle organised crime.
Giuliano Amato, the Italian Prime Minister, said the state 'will know how to respond' to the Mafia on learning of the assassination. 'He (Borsellino) feared that the decree strengthening co- operation between the police and the judiciary and lengthening the time allowed for investigation of the Mafia could not be approved in time by parliament. I say to these assassins and to those at war with the state that these measures will remain. These terrible deaths fill us with grief but strengthen our determination.'
President Oscar Luigi Scalfaro appealed on television last night to his compatriots to unite to defeat the Mafia. Saying that his appeal was 'anguished, deep and insistent', he called on all political and social groups to realise that 'this is the time to defend the credibility of our institutions'.