LONDON Protesters against higher university tuition fees broke into the headquarters of the Conservative party Wednesday, smashing up the glass reception area and streaming up onto the roof.
Protesters scuffled with police and made a bonfire outside the building, a short distance from the Houses of Parliament.
The angry scenes took police by surprise and it was several hours before reinforcements brought the area under control.
It was the first violent protest against 81 billion pounds of spending cuts ordered for the next four years by the coalition to tackle a record budget deficit.
Until now Britain had seen only muted anti-austerity protests compared with those which have rocked other European countries such as France and Greece.
Manchester University student Emily Whitby, 22, one of the protesters who broke into the building, said previous peaceful demonstrations had failed to accomplish anything.
"This isn't a time for polite lobbying, this is a time for action," she said.
Police made 32 arrests and said 14 people were injured, including seven officers. Some rooftop protesters hurled placards and other small objects onto the police below them.
The violence broke out during an otherwise peaceful march by thousands of students and lecturers against government plans to triple the tuition fees universities in England can charge.
Carrying placards saying "Stop education cuts" and chanting "They say cut back, we say fight back," the marchers passed parliament, where politicians will soon vote on proposals to lift maximum tuition fees to 9,000 pounds a year.
"We did not expect this level of violence," the capital's top policeman Paul Stephenson told Sky News. "This was thuggish and loutish behaviour by criminals. It's not acceptable, it is an embarrassment for London and for us."
London Mayor Boris Johnson called for the "full force of the law" to be brought down on those responsible.
"Whatever the merits of the points they are making, there is absolutely no excuse for a tiny minority to engage in acts of savage and unnecessary brutality," he told Sky News.
The National Union of Students (NUS), which helped organise the march, blamed the aggressive action on "anarchists" who had hijacked the protest.
Sophie Farren, 22, a student at London's South Bank University, said the building invasion was stupid. "It makes people less likely to listen to our cause because they will think they are just smashing things because they are students."
Trade unions have forecast there will be large-scale strikes against the deficit cuts, which are expected to lead to half a million public sector workers losing their jobs.
The government plans to cut 2.9 billion pounds of annual state support for universities to help tackle a budget deficit which soared to near 11 percent of gross domestic product following the global financial crisis.
It says the higher student fees, financed by government-backed loans, will cover the shortfall and allow universities to compete against international rivals.
(Additional reporting by Stefano Ambrogi)
(Writing by Tim Castle)