The head of Italy's Senate called on the government to listen to the country's disaffected youth, as anarchists and other hardcore militants threatened to join a rally planned for Sunday. "The hopes and demands of the non-violent should be listened to and deserve the maximum attention," Senate President Renato Schifani told journalists. Schifani, a member of Prime Minister Silvio Berlusconi's centre-right party, called for "collaboration and institutional solidarity" to resolve a "dangerous situation which could result in unacceptable levels of violence." Groups which clashed with police at an "Indignants" protest in Rome last Saturday, in which 135 people most of them officers were injured, have threatened to join another protest on Sunday. This one is near the northern city of Turin, the latest rally against a planned high-speed train line. On a message on their website, the Federation of Anarchists in Turin said they planned to attend, declaring they were "not afraid of police violence, of persecution in the media, or of being arrested." If security forces tried to challenge the group, they added "they will have to choose between shooting us or backing off." Officials have blocked off the surrounding area and 1,600 police officers will be monitoring the demonstration, which organisers insisted would be peaceful. "Ours is a call to Italy because this is a fight that concerns the country's economy and the environment," one of the organisers, Stefania, told ANSA news agency. "Italians are answering en masse and they want the truth," she added. Police on Saturday evening arrested a 23-year-old male who was heading to Turin to join Sunday's demonstration, according to Italian media reports. The youth, named as Leonardo Vecchiolla, has been charged with attempted murder after he was identified in photographs taken during the Rome riots as he pelted officers with rocks before setting a police van ablaze. Politicians spent much of this week blaming each other for the previous weekend's riots. The opposition attacked the government for poor police management, while Berlusconi's allies denounced the violent extremists of the left. The head of the Puglia region, left-winger Nichi Vendola, warned that the militants would be able to "recruit others thanks to the growing desperation of the younger generation and an ineffective state. "The plight of temporary workers, the lives precarious workers lead, that is the principal problem" behind the violence, he told La Repubblica newspaper. The rioters at last weekend's Rome demonstration only numbered between 500 and 2,000 at Rome's riot according to official reports -- a fraction of peaceful protesters, who numbered between 100,000 and 200,000. But Vendola said that the group of violent protesters "is not yet an armed (political) party, but it risks becoming one." Sunday's protest at Susa, near Turin, is organised by the No Tav (No to high-speed trains) movement. But their demonstrations have been infiltrated by violent activists in the past. France and Italy signed a deal in 2001 on building a line through the area, a strategic link in the European network that would cut travel time between Milan and Paris from seven to four hours. The cost has been estimated at 15 billion euros (21 billion dollars). But residents of the Susa Valley have fiercely opposed the plan, saying the construction of tunnels would damage the environment. Clashes between protesters and police in July at the work site at Chiomonte left at least 188 officers and about a dozen demonstrators hurt.