A Russian judge has convicted eight people of assaulting police during a 2012 protest against Vladimir Putin, as hundreds of supporters outside were themselves arrested for demonstrating against the decision.
Outside the courthouse on Friday, police pushed into a crowd that had gathered to support the defendants, grabbing people and hauling them away as others shouted "Shame!", Reuters news agency reported.
Activists called a "show trial" designed to make clear the president would tolerate no dissent. Police said they detained about 200 people for attempting to violate public order.
The convictions, which were widely expected, coincided with political protests in neighbouring Ukraine against its president, Viktor Yanukovich, where dozens have died. Those found guilty face up to 10 years in prison.
Sentencing was postponed until Monday, meaning it will be revealed after Sunday's close of the Sochi Winter Olympics, a prestige project for Putin, who has faced criticism from the West for his treatment of dissenters but says he does not use the courts as a political tool.
The eight were convicted of rioting and assaulting police during an opposition protest on May 6, 2012, the eve of Putin's inauguration to a third term as president.
Two women from protest band Pussy Riot were in the crowd outside, as was Alexei Navalny, an opposition leader who is serving a five-year suspended sentence after a trial last year he said was Kremlin revenge.
Prosecutors asked for prison sentences of five to six years for the defendants, who pleaded not guilty and blame police for clashes that erupted at the rally - part of a series of protests that were the biggest of Putin's long rule but failed to prevent his return to the Kremlin after four years as prime minister.
Sergei Udaltsov and Leonid Razvozzhayev, from the Left Front movement, face up to 10 years in prison as they are charged with organising mass riots and colluding to commit a crime.
The former oil tycoon, Mikhail Khodorkovsky, who was widely seen as a political prisoner during more than 10 years in jail, said the defendants were victims of a "show trial".
"Almost no one doubts that the verdict will be vindictive and cruel," Khodorkovsky, who was flown out of Russia on the day of his release in December, said in a statement on Thursday.