The three main leaders of Russia's opposition movement faced court hearings Tuesday after being released from police custody following a mass protest against Vladimir Putin's presidential election win.
The popular blogger and anti-corruption fighter Alexei Navalny said he was among dozens of protesters held for most of the night by Moscow police after they had arrested 250 people on Moscow's central Pushkin Square.
Another 300 arrests were made in Russia's second city of Saint Petersburg on Monday during a day of protests against an election that secured a third term term as president for Putin.
European observers said Sunday's election was skewed in Putin's favour from the start.
"I have to go to court today at 10.00 am (06:00 GMT)... but I'm feeling pretty sleepy," radical leftist leader Sergei Udaltsov tweeted on Tuesday.
Navalny and Udaltsov were charged with administrative offences that carry 2,000-ruble ($70) fines while fellow opposition member Ilya Yashin could face 15 days in jail after being charged with disobeying the rules for staging a rally.
Police said they arrested 250 people in Moscow and 300 in Saint Petersburg on Monday after moving in roughly to break up rallies claiming that the polls the previous day were rigged.
Some 20,000 anti-Putin protesters turned out on Pushkin Square chanting "Russia Yes! Putin No!". Most of the rally broke up peacefully but police moved in to disperse hundreds of people who refused to leave the square.
The protests came after official results showed Putin had won just under 64 per cent of Sunday's ballot to take back the Kremlin seat he held for the maximum two terms from 2000-2008 before his four-year stint as prime minister.
- Agence France Presse