Hundreds of people attempted to hijack today's main anti-cuts demonstration to wreak havoc in London's West End.
The Met revealed 202 people were arrested for a variety of offences, including public order offences, criminal damage, aggravated trespass and violent disorder.
There were 35 reported injuries over the course of the day, including five police officers.
Sixteen were taken to hospital, including one officer.
Police were attacked as they tried to stop activists smashing their way into banks and shops.
Their action was in stark contrast to and separate from the main TUC rally in Hyde Park which was good natured and passed off peacefully.
Campaign group UK Uncut claimed around 200 of its supporters forced themselves into luxury store Fortnum and Mason - known as the Queen's grocer.
A spokesman for the demonstrators said the target was chosen because "they dodge tens of millions in tax".
Branches of HSBC, RBS, Santander and Topshop were among those to have their windows smashed.
Police spent hours following the mob as they caused damage throughout the UK's busiest shopping district.
Commander Bob Broadhurst, who led the police operation, said: "I wouldn't call them protesters. They are engaging in criminal activities for their own ends."
He added: "We anticipated there would be some problems. We have minimised the damage caused.
"We'll never have enough officers to protect every building in central London. It cannot be done."
Despite the widespread disruption, just nine arrests were made.
Commander Broadhurst said the demonstrators, many of whom were dressed head-to-toe in black and covered their faces, were in small groups and "quite mobile".
"It's been hard to get hold of them," he said.
But he added that video evidence would be used in an attempt to make arrests in the coming days.
Of the nine arrests that were made, four were for using threatening or insulting words or behaviour, three for criminal damage, one for violent disorder and one for going equipped with intent to cause criminal damage.
The protesters surged along Piccadilly, Regent Street and Oxford Street, chanting "welfare not warfare" as they blocked traffic and forced shops to close.
Paint, fireworks and flares were thrown at buildings, while the outnumbered police were attacked with large pieces of wood.
Scotland Yard said lightbulbs filled with ammonia were also thrown at their officers.
The police often had to step aside as the activists continued their destruction.
Four officers were treated for minor injuries and one was taken to hospital with a groin injury.
The Ritz, a Porsche showroom and a Lloyds TSB branch also suffered damage which continued into the night.
A spokesman for civil liberties group Liberty said: "The demonstration appeared to have been infiltrated by violent elements who periodically separated from the main route in order to attack high profile commercial properties and the police before melting into the demonstration once more.
"This minority presented significant challenges for the police and trade union stewards alike and at times jeopardised both the safety and ability to protest of those with peaceful intent."
Policing minister Nick Herbert said the main TUC rally had been a "testament to the British model of policing" and he condemned the violence in the West End as "completely unacceptable".
"Unfortunately a small minority of individuals were intent on disorder," he said.
"I want to be absolutely clear that the blame for the violence lies squarely and solely with the perpetrators and to express my gratitude to those police officers who put themselves in harm's way.
"This Government has been clear that we are committed to supporting peaceful protest but we are equally clear that violence and destruction of property is completely unacceptable."
Shadow home secretary Yvette Cooper said the behaviour of the rioters had been "criminal and dangerous".
"Today's peaceful demonstrators who marched to protect their families, jobs and services will be appalled and disgusted tonight to see TV pictures of some thugs and idiots who have chosen today to launch violent, criminal attacks against the police and property in central London," she said.
"The mindless violence and criminal damage caused by these people is disgraceful and deserves to be met by the full force of the law."
Register for free to continue reading
Registration is a free and easy way to support our truly independent journalism
By registering, you will also enjoy limited access to Premium articles, exclusive newsletters, commenting, and virtual events with our leading journalists
Already have an account? sign in
Join our new commenting forum
Join thought-provoking conversations, follow other Independent readers and see their replies