Student protests in central London took a violent turn on Wednesday, as dozens of protesters broke into Conservative Party headquarters, prompting battles with the police.
Thousands of protesters have occupied the concourse in front of the building, lighting a giant bonfire, reports the London Evening Standard.
Both unions attempted to distance themselves from the violence. The student union posted a message on its Web site condemning the "violent idiots undermining" the message of what it said were 50,000 protesters.
"The people who organized the splinter protest are not known to us," said Ben Whittaker, vice president of the National Union of Students. "We don’t think they’re students. It could be anarchist groups, who’ve obviously been planning this for some time."
Dan Ashley, a spokesman for the University and College Union, which represents faculty members, echoed the sentiment. "It has nothing to do with us," he said.
Earlier in the day, the deputy prime minister, Nick Clegg, a Liberal Democrat, had a heated exchange in Parliament over the government's plans for universities, reports the BBC. Liberal Democrats formed a coalition government with Conservative politicians after the general election in May.
The student union has promised to hold to account Liberal Democrats, who pledged before the election to oppose any plans to raise tuition, with its president saying the union would attempt to force interim elections to unseat members of Parliament who reneged on their promise.