Tens of thousands of opposition supporters have marched through Moscow in the first major protest against President Vladimir Putin in three months.
The opposition says parliamentary elections last December were fraudulent and dispute Mr Putin's re-election in March, the BBC reports.
Demonstrators also demanded the release of three members of the band Pussy Riot, who were jailed in August for two years after staging an anti-Putin protest in a cathedral.
The BBC's correspondent in Moscow says this is the sixth big march there in less than a year, and while not as big as some others, it shows the mood against Mr Putin is still strong in the city.
Addressing the crowd, prominent opponent Alexei Navalny urged protesters to keep up the pressure on the authorites.
Mr Putin has taken a tough line against the opposition since he began a third term as president this year.
He approved legislation increasing fines for those who violate protest laws in June.