Riot police broke up an unsanctioned rally in central Moscow on Monday against the election of Kremlin-backed Dmitry Medvedev in Sunday's presidential polls, briefly arresting dozens of protesters, including Union of Right Forces leader Nikita Belykh and rights activist Lev Ponomaryov.
Medvedev won a landslide victory in the polls, receiving just over 70% of the vote.
"I see in this a strange and not entirely appropriate overreaction," Vladimir Lukin said at a news conference in Moscow. "I see fear in this," he added.
Lukin said he was surprised by what he called an unnecessarily heavy police presence. He said the numbers of police at the rally made it appear as though the city was facing an enemy attack. "I looked around and saw no enemies," Lukin commented.
Belykh told reporters on Monday the city's refusal to allow the protest to go ahead was illegal.
Mikhail Solomentsev, first deputy spokesman for the Moscow Mayor Yury Luzhkov, said police had behaved appropriately.
A similar march took place in Russia's second city of St. Petersburg. The 3,000-strong march was attended by a host of opposition figures, including former world chess champion Garry Kasparov and radical writer Eduard Limonov, founder of the now-outlawed National Bolshevik Party.
Protestors called Sunday's polls undemocratic and "a farce," citing among other complaints the refusal of Russian electoral authorities to register a number of candidates, including the former Russian prime minister, Mikhail Kasyanov.
The opposition also complained of unequal access to the media and the use of administrative resources in favor of Medvedev.
Europe's main election watchdog, the OSCE, boycotted the polls over restrictions it said were imposed by Russia. The head of the PACE monitoring group said Sunday's vote was a "reflection of the will of the electorate, whose democratic potential unfortunately has not been tapped."