By Christian Fraser
BBC News, Rome
The historic centre of Rome has been brought to a standstill by a protest with a difference.
The protest cost £15,000
Authorities took several hours to clean it up - but the stunt has brought huge publicity to the man who staged it.
Visitors to the Spanish Steps on Wednesday were greeted by a rather peculiar sight.
For most of the morning street cleaners and smartly uniformed policemen were chasing little brightly coloured balls, armed with dustpans and brushes.
To everyone's amazement half a million of these balls were suddenly bouncing down the steps.
Within minutes, the famed Piazza de Spagna resembled a children's playground.
The joke was largely on the policemen.
It was another colourful stand from Graziano Cecchini, a man who protests against government incompetence in the most unusual ways.
Last year he poured a dye into the Trevi Fountain, turning it red.
This latest stunt cost him £15,000 (20,000 euros) - and probably a rather large fine.
Tourists grabbed the balls as mementoes at the base of the steps.
When Mr Cecchini finally appeared, walking down the steps with balls bouncing around him, he said he had done it to raise the profile of Burma and the Karen people.
The Karen are a minority who have fought for an independent state since 1949, and accuse the military junta of ethnic cleansing.
The city's head of security, Jean Leonard Touadi, said it was all quite unacceptable.
To err is human, he said, but to persevere is diabolical. And to get publicity at the city's cost was just not funny.
He is probably right - but then it does seem to work.