Russian riot police have broken up a rare opposition march in St Petersburg.
Dozens of protesters were detained, Russian police say
Several thousand opposition supporters gathered to protest against what they see as attempts by President Vladimir Putin to stifle democracy.
They broke through a police cordon and marched down Nevsky Prospekt, the city's main street, shouting "freedom!" and slogans hostile to Mr Putin.
The organisers say police beat demonstrators with batons and made a number of arrests.
The event - entitled "the march of the dissenters" - was organised by opposition leaders, including former Prime Minister Mikhail Kasyanov and chess champion Gary Kasparov.
They accuse the Kremlin of using its power to silence the opposition in advance of local and parliamentary elections.
Mr Kasparov said about 5,000 people took part in the march and called it a "major success".
Officials say between 2,000 and 3,000 took part and several dozen were detained.
The constitution requires Mr Putin to step down after his second term in 2008. Critics accuse him of trying to manage victory for a successor of his choosing.