Thousands of protesters chanting Russia without Putin took to the streets of Moscow and St Petersburg on Monday to challenge Vladimir Putin's victory in a presidential election which international monitors said was unfair.
Putin, who secured almost 64 percent of votes on Sunday, portrayed his return for a third term as president as a strong mandate to deal with the protests although the Kremlin made some
conciliatory moves towards the opposition that were ignored.
Police detained at least 50 people at an unsanctioned rally of about 3,000 people in St Petersburg, witnesses said. Police said they had detained 50 in central Moscow but allowed a protest by thousands more people to go ahead nearby.
Yesterday was not a vote. Yesterday was a falsification. Tell me, was that an election? Boris Nemtsov, a liberal opposition leader, told the rally in Moscow's Pushkin Square, where Soviet-era dissidents used to stage protests.
The crowd, waving flags and anti-Putin banners, roared back: No!
They fear us ... but we do not fear these monsters, Nemtsov said.
Hundreds of Putin supporters staged rallies closer to the red walls of the Kremlin, singing songs, waving Russian flags and chanting the prime minister's name.
A Reuters reporter saw several people being manhandled as police took them away when they protested near the former headquarters of the KGB security police, where the police said they had made 50 arrests.
Before the protests, vote monitors from the Organization for Security and Co-operation in Europe echoed the opposition's complaints that the election was slanted to favour Putin.
The point of elections is that the outcome should be uncertain. This was not the case in Russia, Tonino Picula, one of the vote monitors, said on Monday. According to our assessment, these elections were unfair.
French Foreign Minister Alain Juppe said the election had not been exemplary to say the least.
Tiny Cox, one of the most senior electoral monitors, said there had been some improvements from a parliamentary poll which observers said was marred by irregularities on December 4.
We did not see the violations we saw in December. We saw far less cases of ballot-box stuffing, he said.
But the OSCE monitors said Putin still had an advantage over his rivals in the media and that state resources were used to help him extend his domination of Russia for six more years.
Expressing concerns which a European Union spokeswoman said were shared by the 27-country bloc, the monitors called for all allegations of irregularities to be thoroughly investigated.
Although the observers' findings have no legal bearing, they undermine Russian election officials' statements that there were no serious violations.
They would also support some in their view that elections ultimately have little real significance in Russia; that power is something tightly controlled and divided up by a largely stable ruling clique, as demonstrated by the 'tandem' power deal struck by Putin and current president Dmitry Medvedev in 2008.
I used to love Putin, like any woman who likes a charismatic man. But now I think he is getting senile. Nobody can stay in power forever, Vasilisa Maslova, 35, who works in the fashion trade, said during the opposition rally.
Voting yesterday, I felt like I was choosing the least dirty toilet in a crowded train station.
Putin's opponents, fearing he will smother political and economic reforms, have refused to recognise the result, which could allow the former KGB spy to rule Russia for as long as Soviet leader Leonid Brezhnev, accused of presiding over the years of stagnation.
Putin, 59, has already served as president or premier for 12 consecutive years and made way for his ally Medvedev in 2008 only because of constitutional limits.
He (Putin) is forcing things to breaking point. He is declaring war on us, said journalist Sergei Parkhomenko, one of the protest organisers.
In a conciliatory move, Putin invited his defeated presidential rivals to talks, although Communist Party candidate Gennady Zyuganov did not attend.
The Kremlin also took steps that appeared intended to try to take the sting out of the protests which began over the December 4 poll won by Putin's United Russia party.
Medvedev, who will stay in office until early May, told the prosecutor general to study the legality of 32 criminal cases including the jailing of former oil tycoon Mikhail Khodorkovsky.
Khodorkovsky, who headed what was Russia's biggest oil company, Yukos, and was once the country's richest man, was arrested in 2003 and jailed on tax evasion and fraud charges after showing political ambitions and falling out with Putin.
The Kremlin said Medvedev had also told the justice minister to explain why Russia had refused to register a liberal opposition group, PARNAS, which has been barred from elections.
The order followed a meeting last month at which opposition leaders handed Medvedev a list of people they regard as political prisoners and called for political reforms.
Medvedev's initiatives have only one goal: To at least somehow lower the scale of dismay and protest that continues to surge in society, Zyuganov said.
The move could be a stalling tactic to appease the organisers of the biggest protests of Putin's rule, or a parting gesture by a man intent on making his mark.
Many voters still see Putin as a safe pair of hands and credit him with restoring order after the chaotic 1990s under President Boris Yeltsin and overseeing an economic boom.
But others have lost all faith in elections and see Putin as an impediment to Russia having a fair, decent society.
We've had enough lies. The whole country has had enough lies, said Rosa Trukachova, a 60-year old pensioner.
(Additional reporting by Thomas Grove and Jennifer Rankin, writing by Timothy Heritage)