Police in central London are on alert for possible further unrest after a day of violent protests by G20 demonstrators.
Around lunchtime, riot police had to be sent in after activists attacked a uniformed officer and stormed a branch of the Royal Bank of Scotland in the City, London's financial district.
A handful of people with black scarves obscuring their faces and hoods over their heads smashed a hole in the windows with a metal pole and crawled in.
Protesters removed equipment, painted graffiti on the walls, threw a chair through a window and started a small fire.
Police entered the branch at around 2 p.m. and shortly afterwards began driving demonstrators away from the Threadneedle Street branch, which had earlier been closed by RBS.
Officers on foot backed up by mounted officers lined up outside the building as smoke bombs were thrown by a baying crowd. At least one police officer was hurt as the RBS branch became a flashpoint.
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London Bankers Dress Down to Blend In.
More than 4,000 demonstrators, most of them peaceful, had gathered near the Bank of England to demand action from world leaders ahead of the G20 summit.
But several hundred clashed with police, who were pelted with eggs, paint bombs and empty beer cans.
Scotland Yard responded by cordoning off streets and sending in riot police and officers on horseback.
It said later at least 24 arrests were made Wednesday in connection with the protests.
Two people were held for aggravated burglary over the raid on the RBS building and two for public order offences.
Others were held for threatening behavior, possession of drugs, violent disorder and blocking a road.
Anger at bankers' role in the global economic downturn and frustration at slow progress in tackling climate change prompted thousands to take to the streets in the capital.
Four protest marches converged on the Bank of England after setting off along separate routes as helicopters circled overhead.
City workers leaned out of windows and waved £10 notes at demonstrators on the streets below, who responded with jeers and shouts.
Sky News security expert Crispin Black said he was very impressed with the way police had defused the situation by refusing to rise to provocation.
"I think the police have been very skilled," he said. "The way they moved people away from the RBS branch was very clever, and the way the temperature has cooled down there is testament to their skill."
Most bankers dressed down to avoid confrontation with demonstrators, swapping their suits for casual clothes.Most bankers dressed down to avoid confrontation with demonstrators, swapping their suits for casual clothes.
Most bankers dressed down to avoid confrontation with demonstrators, swapping their suits for casual clothes.
Some were told to stay at home, others that they should bring lunch with them to the office.