MOSCOW (AP) - Vladimir Putin's chief political foe was convicted along with his brother on Tuesday in a fraud case widely seen as retribution by the Kremlin, setting off one of Russia's boldest anti-government demonstrations in years.
Police allowed the unsanctioned protest by several thousand people to proceed just outside Red Square for about two hours before moving in to push the rally away.
The demonstration came hours after Alexei Navalny, an anti-corruption campaigner, was found guilty of fraud and given a suspended sentence of 3½ years. His brother was sent to prison.
The convictions are widely seen as a political vendetta by President Putin, who has shown little tolerance for dissent during his 15-year rule.
Navalny, who has been under house arrest since February, broke its terms to attend the rally and was rounded up by police as he approached the site. He later tweeted that police drove him home and blocked him from leaving his apartment.
The protesters, who gathered on the square, chanted: "We are the power!" and "You won't be able to jail us all!" Some shouted slogans of support for Ukraine, which saw its Crimean Peninsula annexed by Russia in March and has faced a pro-Russia insurgency in the east.
Alexei Mayorov, a security official in the Moscow mayor's office, had warned any attempt to hold a rally would be quickly blocked, but police allowed it to proceed for a while before pushing the protesters toward subway entrances. Police said they detained about 100 protesters.
Russian law requires demonstrators to receive official clearance for their actions and can impose heavy fines and prison sentences for those who disobey.
The provocateur punk group Pussy Riot had released a video supporting Tuesday's demonstration, featuring four stylishly dressed women sweeping snow from the square, then mounting their brooms and flying off as witches across the Kremlin wall in a performance symbolizing protest.
Two of the performers, Nadezhda Tolokonnikova and Maria Alekhina, spent nearly two years in prison on charges of hooliganism for mounting an anti-Putin protest in Moscow's main cathedral in 2012, and won global fame.
Tuesday's verdict had been scheduled for next month, but the court session was abruptly moved forward to the day before New Year's Eve, the main holiday in Russia, in what was widely seen as an attempt to head off protests. Russia's main nationwide state-controlled television stations refrained from reporting the verdict.
In Washington, State Department spokesman Jeff Rathke said the U.S. government is troubled by the verdicts against the Navalny brothers.
"The decision is a disturbing development in our view, and it appears to be designed to further punish and deter political activism. This appears to be another example of the Russian government's growing crackdown on independent voices," Rathke told reporters.
"And we also continue to be concerned about increasing restrictions on independent media, civil society, minority groups and the political opposition. We believe that the Russian people ... deserve a government that supports an open marketplace of ideas, transparent and accountable governance, equal treatment under the law, and the ability to exercise their rights without fear of retribution."
A European Union spokeswoman said the charges against the Navalny brothers hadn't been substantiated during trial and the guilty verdict against them "appeared to be politically motivated."
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