Putin opponents march in Moscow

Anti-government protesters have begun marching in Russia's capital Moscow, ahead of a major rally to demand fresh elections and a new president.

The protest, on a national holiday, comes a day after police raided the homes of several prominent activists.

They were all ordered to report for questioning on Tuesday, and so were likely to miss the march.

Last week, President Vladimir Putin signed a new law increasing fines for those who violate protest laws.

Activist Anatoly Katz told the BBC he has been secretly filming the protest to get his own crowd count from the demonstration.