Police hunting those responsible for violence and criminal damage during student protests released images today of a man throwing a petrol bomb.
The hooded figure can be seen running across Parliament Square with what appears to be a petrol bomb.
The video was recorded by a member of public during one of the most violent days of demonstrations on 9 December.
Investigators have also obtained images of a second suspect attacking cars in a royal convoy in Regent Street on the same day.
He was also caught on camera kicking in the windows of a branch of Topshop in Oxford Circus and throwing a metal fence at police officers.
A further 10 still images have been released of people suspected of violence and other offences on November 24.
Senior officers at the Met have formed a specialist unit, dubbed Operation Malone, to bring those who broke the law to justice.
They have arrested more than 200 suspects, the majority in their late teens and early twenties, since the first protest on November 10.
Police also want to trace a friend of the man involved in the trio of incidents, including the Royal convoy attack.
The suspect was wearing a dark jacket with white stripes down the arms and a brown scarf over his mouth.
The latest appeal follows the imprisonment of Hampshire student Edward Woollard for throwing a fire extinguisher from the roof of the Millbank complex.
The 18-year-old was jailed for 32 months after admitting violent disorder during the first outbreak of student protest disorder.
Detective Chief Superintendent Matthew Horne, who is leading the inquiry, said: "The right to peaceful protest is fundamental.
"The Met polices thousands of public events each year and makes significant efforts to engage with organisers to ensure the safety of everyone.
"What we have released today is the unlawful side of protest. An individual throws what appears to be a petrol bomb, putting others in clear danger.
"Another young man is seen committing acts of suspected violent disorder in Parliament Square, attempting to cause damage to shops and attacking the Royal Convoy.
"We saw, this week, a young man with no criminal history sentenced to a substantial term of imprisonment for throwing a fire extinguisher off the roof of Millbank Tower.
"This clearly could have resulted in catastrophic injury to those below him. His actions and their consequences have also had a massive impact on his family.
"I would urge those intent on committing violence and damage to reflect upon this."
:: Anybody with information should call 0208 358 0100 or Crimestoppers, anonymously, on 0800 555 111.