British Prime Minister David Cameron has condemned the actions of students who stormed his party's London headquarters in protest over plans to increase tuition fees.
Mr Cameron also criticised the 'inadequate' police response, saying there had only been a small number of officers deployed to protect the building housing the Conservative party's offices when the riots broke out.
At least 14 people were injured and about 35 arrested after thousands of demonstrators besieged the office building, smashing their way through the glass frontage and wrecking the lobby.
Police admitted they had been unprepared for the violence and had been expecting a peaceful demonstration.
The National Union of Students said up to 50,000 people took part in the march.
NUS President Aaron Porter condemned as 'despicable' the actions of the minority who attacked the Millbank building.
Mr Cameron said this morning that those responsible should be prosecuted.
He said: 'Of course people have a right to protest peacefully, but I saw pictures of people who were bent on violence and on destruction and on destroying property and that is completely unacceptable.
'We need to make sure that that behaviour does not go unpunished and we need to make sure that we don't, as the police put it, see scenes like that on London's streets again.'
Mr Cameron said he followed the unrest on television and had telephoned colleagues to check the safety of those in the building.
He said: 'So I was on the telephone. I wanted to know what was happening. I wanted to know that people were safe.
'I was worried for the safety of people in the building because I know people who work in there, not just the Conservative Party but other offices as well.'
Half of those injured in the violence were police officers. One female officer was seen being led away from the scene with blood on her face.
Police response
Mr Cameron said he agreed that police had lessons to learn on how they handled the protest.
'They were very brave, those police officers, but as the police themselves have said, there weren't enough of them and the police response needs to reflect that,' he said.
London's police chief Paul Stephenson has promised a full investigation.
Mr Stephenson said: 'This level of violence was totally unexpected; we need to ask ourselves why. It's an embarrassment for London and for us.'
Mr Cameron insisted that the new fees structure - under which universities can charge up to £9,000 a year for tuition and graduates will pay the money back over their working lives - was 'a more progressive system than the one that it will replace'.
He added: 'I think the right place for the debate and argument to take place is in Parliament, is in debates rather than the scenes that we saw.'
Mr Cameron also rejected suggestions by some of the protestors that they signalled a throw-back to the riots of the 1980s, which targeted Margaret Thatcher's Conservative government.
'I think there's a very big difference to the 1980s. This time we have a coalition government, we have two parties that have come together in the national interest,' he said.
He added: 'I think most people understand we have to take these steps, we have to get Britain out of the (economic) danger zone.'
