Anti-terrorism experts from six countries yesterday began a hunt for hundreds of members of an "anarcho-insurrectionalist" group thought to be behind the recent wave of mail bombings aimed at European institutions.
The lawyer at the heart of the inquiry dismissed speculation that a lone maniac could be responsible.
Mr Enrico Di Nicola, the chief prosecutor of Bologna, where the packages were dispatched, said membership of the organisation "may be about 350 in all of Italy".
European Union offices were yesterday on a state of high alert after the delivery of seven explosive devices in nine days, all from Bologna.
In Brussels, bomb disposal experts rushed to Italy's mission to the EU after a suspect letter was found, but officials said it was a false alarm.
One of the latest batch of packages containing explosives was addressed to Gary Titley, leader of the British Labour members of the European Parliament.
Soon after it was found on Monday, the interior ministry in Rome announced the setting up of a multi-national task force charged with identifying the terrorists behind the mail attacks within a period of two months.
The move followed a meeting attended by anti-terrorist specialists from Italy, Spain, Greece, the Netherlands, Germany and France.
The most obvious clue for investigators points to a group calling itself the Informal Anarchic Federation (FAI), which claimed responsibility for two minor blasts near the home of the head of the European Commission, Romano Prodi, six days before Mr Prodi's wife became the first recipient of an exploding package.
The FAI said it had brought together four shadowy groups, including one that had claimed responsibility for a failed bomb attack in Bologna during the 2001 clashes at the G8 summit in Genoa.
Mr Di Nicola described the FAI as made up of "individualists who don't accept any type of organisation, structure or centralisation of decision-making".
The group's initials evoke those of one of the most influential historical anarchist groups, the Iberian Anarchist Federation.
But few mainstream anarchists would describe themselves as "anarchic", and some in Italy have suggested that the FAI is a front.
In a country whose own intelligence services were deeply involved in the fomenting of subversive violence in the cold war period, many people need convincing that extremists are who they say they are.
- (Guardian Service)