Violent clashes have erupted in the shadow of Parliament as thousands of protesters laid siege to the seat of power.
Thousands of demonstrators flooded Westminster as MPs gathered inside the House of Commons to debate plans to treble university fees.
They were met by hundreds of police dressed in protective equipment and arranged in lines up to four deep behind reinforced metal fencing.
Officers were pelted with bottles, placards and paint as a flare was thrown and roadwork barriers uprooted.
One group of protesters wore distinctive green hard hats and used foam placards shaped like books to jostle with police and protect themselves.
Hundreds more police, including officers on horseback, could be seen being held in reserve on nearby Westminster Bridge.
Students marched from universities and colleges across London, converging at Trafalgar Square before marching on to Parliament.
The crowd was mainly made up of students, but lecturers, parents and other members of the public also joined the throng. Trade union banners were evident among the crowd including Unison, the Rail Maritime and Transport (RMT) union and the Public and Commercial Services union.
Meanwhile inside Westminster, there is speculation that up to half of the Liberal Democrat MPs could rebel against the Government despite frantic efforts to prevent a major split in the coalition.
Liberal Democrat leader Nick Clegg earlier branded opponents of tuition fee rises as “dreamers” and insisted he is not ashamed of backing the plans because he is dealing with “the way the world is”, but Labour leader Ed Miliband urged Lib Dem MPs to stick by their pre-election pledge and vote against the increases.