The government called on Thursday for peaceful protests in Vicenza at the weekend amid fears that a planned demo against the expansion of a US military base in the northern city could turn violent.
Organisers said as many as 50,000 people would march on Saturday. Groups taking part include pacifists, political leftists, some trade unions, environmentalists, anti-globalisation activists and Vicenza residents who back the local campaign against the base.
"I'm counting on wise behaviour," said Premier Romano Prodi. "There's no reason why the demo should not be peaceful".
Interior Minister Giuliano Amato has warned that Saturday's demonstration could be seen by subversive groups as a chance to battle with police. Radical groups like the 'Black Bloc' could try to hijack the march, authorities fear.
The United States embassy in Rome has advised Americans in Italy to avoid Vicenza and the base over the next few days so as not to become "targets for anti-American protestors".
Meanwhile, the local council has announced that, owing to the possibility of "high tensions", schools will be closed for the day.
The centre-right opposition said on Thursday that the outcome of the Vicenza demo would show whether Prodi's hard-line communist allies were able to draw a clear line between themselves and violent groups allegedly acting around their fringes.
Prodi's government recently angered some of his more leftist allies by giving definitive approval for the expansion project to go ahead.
Several MPs from parties supporting his administration are expected to march in Vicenza, including possibly the leaders of two Communist parties.
The premier has made it clear he wants no members of his government to take part in protests, saying it would mean the government was protesting against itself.
Party of Italian Communists leader Oliviero Diliberto justified his presence in Vicenza by saying the demonstration was "not against" the government, but a form of "stimulus" for it.
Welfare Minister Paolo Ferrero, a prominent member of the Communist Refoundation Party, said that the people protesting at the weekend would actually be striking a blow against extremism and left-wing domestic terrorism.
Beating terrorism "requires the police, the judiciary and also wide democratic participation. People who protest peaceful against the government are also fighting terrorism," he said.
"The government intends to make sure the demo is absolutely peaceful," Deputy Interior Minister Marco Minitti said on Thursday, voicing the hope that everyone going to Vicenza would share this aim.
