Vandalism to the Conservative Party’s headquarters on Millbank following yesterday’s student protest is set to cost tens of thousands of pounds to fix.

Yesterday, around 50,000 students protested against the government’s plan to charge students up to £9,000 per year for tuition fees from 2012, three times the current annual £3,290 fees. The protest turned violent and there was significant damage to the Conservative office on Millbank.

Thirty-five people have been arrested for offences including criminal damage and aggravated trespass. Metropolitan Police Commissioner Sir Paul Stephenson said the level of violence was “largely unexpected”.

National Union of Students president Aaron Porter said troublemakers had hijacked the protest. Damage to the building included smashed windows, graffiti and damaged furniture, while staff working in the building were barricaded in because of the violence.

Prime minister David Cameron criticised the violence: “People who assault police officers or who smash windows or who break property are breaking the law and yes, those people I hope… will be prosecuted. They should be,” he said.

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