Video: 13 year-olds join Sheffield student fees demo; police van attacked in London

Protesters attacked a Metropolitan Police van close to the Foreign and Commonwealth Office, where they pulled off wing mirrors and daubed it with graffiti.

A handful of young women could be seen attempting to stop further damage as a man urinated on one front wheel. Witnesses said a smoke bomb was thrown inside the van as protesters, some covering their faces

A group of young men leapt on to the roof, smashed the windscreen, daubed it with a slogan and hurled sticks at the vehicle which was parked in the middle of Whitehall, central London.

Meanwehile in Sheffield, around 1,000 students gathered in the city centre, many from schools as well as the two universities.

There were reports of pupils walking out of a number of secondary schools before gathering at Sheffield University Students' Union.

Many in the crowd appeared to be of school age, some as young as 13 or 14.

A line of police guarded the front of the Victorian town hall as the crowd chanted and waved placards. There were also demonstrations in Leeds.

The London mob surrounded the Metropolitan Police van close to the Foreign and Commonwealth Office, where they pulled off wing mirrors and daubed it with graffiti.

A handful of young women could be seen attempting to stop further damage as a man urinated on one front wheel.

Witnesses said a smoke bomb was thrown inside the van as protesters, some covering their faces with scarves, hit the windows with wooden sticks.

Several fireworks were let off nearby, greeted by cheers and whistles, as a light was smashed on the back of the vehicle.

The van was abandoned a short distance from the Royal United Services Institute (RUSI) where Met boss Sir Paul Stephenson has been giving a speech on terrorism.

In other areas of Whitehall there was a party atmosphere, with students jumping up and down to dance music as helicopters hovered overhead.

The protest has been dubbed Day X, with parents, teachers and trade unionists invited to join students.

Many of the rallies have been organised by the Education Activist Network and the campaign group Youth Fight For Jobs.

There were reports that a police officer suffered a broken arm during the scuffles in Whitehall.

An estimated 10,000 students were on the streets of central London to protest against increased university tuition fees.

The demonstration followed a day of action two weeks ago that saw 60 arrested and dozens injured when a riot broke out at the Tory Party headquarters.

Police wanted to avoid a repeat of the chaos that ensued on November 10 when a splinter group attacked 30 Millbank.

They were caught out when the march, organised by the National Union of Students (NUS) and the University and College Union (UCU), turned violent.

Marches have been organised across England and Wales, with school and college students joining the action.

Cities including Birmingham and Manchester were holding rallies, with university workers protesting alongside students.

In Trafalgar Square, central London, several thousand gathered on the steps outside the National Gallery and at the base of Nelson's Column.

They chanted slogans including "Tory scum" and "No ifs, no buts, no education cuts" and carried placards reading "RIP my degree" and "Nick Clegg, shame on you".

In Manchester, where several thousand protesters had gathered, a group of several hundred broke away from the main demonstration and headed towards the town hall.

Around 3,000 protesters had made their way from Manchester University student union shouting "No ifs, no buts, no education cuts".

There were some minor scuffles between protesters and police in Bristol, where around 2,000 people joined a demonstration.

About three dozen police officers were blocking the entrance to the town hall, where protesters were sitting down reading books.

The Lib Dems have come under intense fire over Government plans to charge students as much as 9,000 per year in fees from 2012 after pledging before the general election to oppose any such hike.

Parliament is due to vote on the increase before Christmas.

Police blocked in a large number of protesters in Whitehall close to the junction with Parliament Square, near Westminster Tube.

The tactic, known to police as containment and to protesters as kettling, has been criticised in the past.

There were clashes at a bottleneck entrance to King Charles Street, close to the Foreign Office, where metal barriers were thrown at police.

One injured police officer could be seen being dragged away by colleague brandishing a metal baton.

A Metropolitan Police spokesman confirmed a constable had suffered a broken arm during the protest and no arrests had been made.

He said: "There is a containment on Whitehall to prevent further criminal damage and we will look to disperse anyone being held as soon as we can, when we can ensure that no further criminal damage will be committed elsewhere."

Elsewhere, students carrying anti-cuts banners congregated at Brighton station, watched by police. At the University of Sussex students gathered on campus to listen to speeches.

In Oxford, there were reports that up to 300 students had occupied Radcliffe Camera, which houses Radcliffe Science Library.