Russian riot police have broken up a rare opposition march in St Petersburg. 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...