Police and demonstrators clashed on Monday as students gathered in central Turin to protest a meeting of university chancellors linked to Italy's programme for this year's Group of Eight summit.
Police charged 100 demonstrators blocking roads outside the venue in the morning, prompting an unauthorized march and further tension in the afternoon.
The demonstration broke up late afternoon, after protestors briefly occupied Turin's main railway station, Porta Nuova, and police carried out a second charge.
Two demonstrators and one police officer were taken to hospital with minor injuries.
Three people were arrested during the day. Two of them, a pair of Greek students in Italy for the demonstration, were later released without charge.
A 28-year-old Italian man is still being questioned by police.
The demonstrators, members of a left-wing student group called Ragazzi dell'Onda, said another march would be staged on Tuesday in protest at university representatives participating in a G8-related event.
Figures in the centre-right government reacted angrily to news of the clashes, blaming the ''hard left'' for deliberately provoking violence.
Culture Minister Sandro Bondi pointed the finger at ''an extremely well-organized minority that is ready to turn violent and grabs any opportunity to oppose the institutions and political forces''.
Youth Minister Giorgia Meloni expressed support for student protestors in general but said the Ragazzi dell'Onda movement had been ''cynically hijacked'' by ''so-called anti-globalization protestors''.
A regional representative of Premier Silvio Berlusconi's People of Freedom party said the demonstration should not have been allowed to go ahead.
''There have long been predictions that today's G8 protest would result in public order problems, as a result of violent demonstrators from the hard left,'' said Agostino Ghiglia.
Two of Italy's police unions, SAP and COISP, also expressed anger at the demonstrators.
SAP spokesman Massimo Montebove said police were ''fed up with being kicked, punched and stoned by people interested only in the media attention such incidents attract''.
COISP secretary Franco Maccari said attacks on police officers should carry higher criminal penalties.
But opposition critics focused on police mismanagement of the event and suggested the government was trying to stifle the right to free speech.
Paolo Ferrero, a former minister and leader of the Communist Refoundation Party (PRC), described the charges as ''barbarous and unacceptable''.
''Faced with an entirely peaceful and symbolic protest, the police attacked and injured demonstrators,'' he said, accusing the government of encouraging actions worthy of a ''police state''.
Paolo Cento of the Green party said the police action was ''serious and unacceptable'' and called for the interior ministry to ''put an immediate stop to this repression''.
The youth section of the small Italian Communist Party said the police action demonstrated the ''Berlusconi administration's true nature: that of an openly reactionary and authoritarian government''.
The conference, attended by 41 chancellors from 19 industrialized and developing countries, focused on economics, ethics, energy and ecology in the context of sustainable development.
No politicians or ministers were present at the event, although a message from Italian Premier Silvio Berlusconi, in his capacity as this year's G8 president, was read out.
Berlusconi described the meeting as ''an opportunity for dialogue and fruitful exchange'' and said he hoped it would discuss issues regarding ''community development, starting with education and training''.
The conference aimed to produce a final statement for consideration by G8 leaders at the upcoming summit, taking place in L'Aquila in July.
