A Moscow district court on Monday released the leader of Russia’s opposition Left Front movement, Sergei Udaltsov, and anti-corruption activist Alexei Navalny, who were detained at the May 6 March of Millions, and fined each of them 1,000 rubles ($33.5) for defying police orders.

On Sunday, Udaltsov was led by police off the stage while addressing participants of the rally on Bolotnaya Square. Udaltsov came onto the stage and asked people to stay on the square until authorities fulfilled their demands. "We will not leave," Udaltsov yelled into the microphone, after which policemen escorted him off the stage.

Udaltsov himself did not admit guilt, said he disagrees with the court’s ruling and emphasized that would challenge it.

Navalny, a well-known blogger, said that he had not defied police orders during the rally and accused the police of the unnecessary use of force.

Over 400 people were arrested and scores injured as Sunday’s rally against Vladimir Putin’s rule turned violent when protesters briefly broke through police lines in a bid to take their protest to the Kremlin walls. Putin’s opponents accuse him of corruption and curtailing political freedoms. Protest figurehead Boris Nemtsov, a Yeltsin-era deputy prime minister, was among those detained. A magistrate on Sunday ordered Nemtsov to pay a fine of 1,000 rubles (about $33) for violating rules for public events, while cases of Navalny and Udaltsov were heard on Monday.