G20 SUMMIT:IT WAS billed in advance as the "G20 Meltdown", a public street party which organisers promised would herald "a very English Revolution" right in the financial heart of London.

But while yesterday’s protests outside the Bank of England fell short of outright insurrection, the clashes between police and a small minority of the demonstrators heightened nerves across the city.

Only a few dozen black-clad and masked anarchists were at the forefront of the violence in and around Threadneedle Street, the traditional home of the British financial establishment, but police at times struggled to maintain control.

The most symbolic moment took place some streets away when a group succeeded in breaking into a branch of Royal Bank of Scotland.

Yesterday’s event, which drew an estimated 4,000 people or so, was organised by a disparate alliance of activists campaigning on issues ranging from climate change to global poverty.

Earlier in the morning, police intercepted and arrested 11 activists in an armoured personal carrier, although it was later claimed that the group planned to use it to stage an act of “street theatre”.

The plan to lay siege to the Bank of England was the brainchild of, among others, Prof Chris Knight, a lecturer in anthropology at the University of East London.

A former member of the Militant Tendency which penetrated the British Labour Party during the 1980s, he was suspended from his academic post last week after telling the media the police would get a fight if they wanted one.

A carnival-like atmosphere initially reigned yesterday after four separate marches converged from four different locations in central London behind four horsemen of the apocalypse, symbolising war, climate chaos, land seizures and financial crimes.

On the way to the Bank of England, a non-threatening atmosphere prevailed even when some office workers leaned out of windows and taunted the marches with banknotes. A small counter-protest by a group of young men who said that they were standing in support of free markets vacated Threadneedle Street before the demonstrations converged.

By late morning mobile speakers were blaring out the voice of Bob Marley, while a bag-piper wandered around serenading the crowds. Kristen Forkert, a Canadian student living in London who was holding a pillow bearing the slogan “People Not Property” voiced some typical sentiments: “We are here because it gives us a sense of empowerment and because we think that the cause of the financial crisis is the system itself,” she said.

However, the mood turned ugly at around lunchtime as baton-wielding police police traded blows with some of the masked anarchists.

Police were quick to contain the disturbances, setting up a cordon around the area before allowing groups to leave at intervals in a crowd-control tactic. London’s Metropolitan Police said yesterday evening that more than 20 people had been arrested, including the 11 who were detained earlier in the morning.

Two protests were passing off peacefully, including a rally by thousands of opponents of the wars in Iraq and Afghanistan. It reached Trafalgar Square after marching from the US embassy on Grosvenor Square. The other was an occupation of the European Climate Exchange in Bishopsgate, London, where an encampment was erected by activists from groups include a number who have spearheaded direct action protests at British airports.

A ring of steel will be in place around the Excel Centre in east London today for the G20 summit.