London: Rioting girls became the disturbing new face of violent protest on Thursday. They threatened to overturn a police riot squad van as they smashed windows, looted riot shields, uniforms and helmets and daubed the sides with graffiti.

Police fled the van as the young demonstrators against university tuition fees yelled obscenities only yards from Downing Street. A second wave of truanting schoolgirls who were there for the excitement rather than to cause mayhem then swarmed around the van and posed for photographs taken on friends' cameras and iPhones.

The disgraceful scenes, part of internet-coordinated protests around the country, came despite claims that Metropolitan Police officers were fully prepared this time after violent clashes in Millbank a fortnight ago caused millions of pounds worth of damage.

Scotland Yard deployed more than 1,500 officers —seven times the number on November 10 — to control hordes of students smashing windows of government buildings and scrawling graffiti on the walls.

At least 29 protesters were arrested for theft, violent disorder and criminal damage after a female police officer suffered a broken hand and another officer had to be dragged out from a cordon with leg injuries when violence flared.

Paramedics treated 11 people and nine were taken to hospital.

On Wednesday night some of the student protesters claimed that the violence was directed by truanting schoolchildren.

Lydia Wright, 22, of the School of Oriental and African Studies, said: "It's all gone terribly wrong. It started off as two small groups from my university and UCL.

"As soon as we got down to Whitehall, we were joined by some other people, but I think it was mostly the schoolkids who were creating the trouble.

"They weren't really supporting the cause. Quite a few of them were just wanting to cause a disturbance."

Protest marches

Elsewhere, thousands joined protest marches in Manchester, Liverpool and Brighton as pupils walked out of school in Winchester, Cambridge and Leeds.

Students occupied buildings in Oxford, Birmingham, Cambridge, Plymouth and Bristol, where fireworks were hurled at police horses.

Two protesters were arrested in Cambridge for obstruction, one in Liverpool for egg throwing and four in Manchester for public order offences and obstruction. There were also violent clashes with police in Brighton as students tried to storm council and university buildings in the city centre.

But the most disturbing scenes were in London where a largely peaceful demonstration descended into violence. The trigger was a police riot van that had trailed protesters into Whitehall and stopped between the Houses of Parliament and Downing Street.