An offshoot of Italy's Red Brigades urban guerrilla movement published a 26-page Internet message today saying it had executed a top government adviser and reviving fears of a new era in political killings.
Mr Marco Biagi (52) was shot dead on Tuesday night in the northern city of Bologna with the same pistol that the Red Brigades for the Construction of the Fighting Communist Party had used to kill another government aide in 1999.
Police meanwhile continued to examine video material collected from security cameras around Bologna and focused on the testimony of a witness, who according to Italian media, saw a member of the group in the northern city on the day of the assassination.
The original Red Brigades were responsible for a slew of murders of politicians, businessmen and policemen in the late 1970s and 1980s.
Their most notorious act - the 1978 kidnapping and killing of former prime minister Mr Aldo Moro - aimed to bring down the Italian state but in effect strengthened it by alienating even their sympathisers.
Police believe some of the jailed guerrillas who have not rejected the past still have contacts with the new group and have searched their cells.
In a diatribe against modern capitalism, the new group declared on the Web that "an armed nucleus of our organisation executed Mr Marco Biagi". It accused the Labour Ministry adviser of exploiting workers with the labour reforms he had co-authored.
In a lengthy passage, the group said it approved the September 11th attacks on the United States, calling them a concrete move to contrast imperialist strategies. Police said they believed the message was authentic.
Mr Biagi's killing came amid tension in Italy over plans to change employment laws that have prompted unions to call a general strike.
President Carlo Azeglio Ciampi called for unity and dialogue today to combat the renewed threat of politically motivated violence.