Our reporter Natasha Culzac is at the DemoLition protest, from where she brings all the details about the u-turn it had, coming from a peaceful to a violent protest.

Everything started calmed, but the anger from students drove them to the violent situation of smashing windows and starting bonfires. Protesters were pushing doors and windows to force their way into Millbank Tower at Central London.

Policemen were seriously injured and are in need of more officers in order to get the situation under control.

Miss Culzac said: "The fire's being fanned by protesters with effigys being burned and branches.

"Riot police are trying to hold off protesters trying to get in HQ but apparently, around 200 students have already entered and stopped by the police."

Miss Culzac says that musicians are playing drums and people are dancing. Chants include: "No ifs no buts,no education cuts" and "Build a bonfire, put the Tories on the top, put the Lib Dems in the middle and we'll burn the f*cking lot".

Students got to the roof and flying flags were on the top of the building. They are out of control.

Media is wondering where are the policemen, if this is not the first time that Central London sees such a huge demonstration. However, there are plenty of them all over the area, but not enough for the number of students that are destroying everything that gets on their way, windows, computers, chairs, tables and even officers.

The raise of tuition fees of up to 9000 is a worry for every generation, and the best way to let the government know about citizens' unhappiness about this is by hitting the streets peacefully. But there's no need of breaking every single rule and acting in an illegal way. 

The current picture of the scene is breaking glass on the floor, spray painting at the reception of the building and protesters throwing stuff such as newspapers, concrete and fire off the roof, while people at the bottom are screaming: "Stop throwing sh*it, stop throwing sh*t."

Small fires are all over the area and the reception area at the ground floor of the Millbank Tower is completely destroyed.

Illegal actions have brought injured policemen and other students as a result of their actions.

NUS is disappointed about the fact that students are breaking into such a violent situation instead of keeping a peaceful atmosphere.

Amanda, a protester that called Sky News, said: "I took the risk of coming to the roof. I'm not a student. But, this is not a matter of only students, it is matter of everyone as this will also affect my children".

The main worry of this violent situation is that after such a huge and successful gathering over 40,000 students from all over the country, then the main news would be students' anarchy, instead of tuition fees.

Former City SU President, Nikhil Cumlajee, posted on Twitter: "Yes a lot went wrong but don't miss the message! The demo was amazing protest saw thousands of students come together for one common cause down with tuition fees!"

Check out some striking images from BBC here!