John Bacon

USA TODAY

Thousands of demonstrators across Russia marched Sunday to protest corruption in the government of President Vladimir Putin, and the opposition leader was among hundreds arrested.

Alexei Navalny was among about 500 people arrested in Moscow, police said in a statement. Navalny was charged with violating an administrative code regulating public gatherings and faced a possible fine, community service or administrative detention, the state-owned TASS news agency reported. Most of those detained were released within hours, police said.

"Many people were detained today," Navalny tweeted, warning the "thieves" that "we are millions."

Scores of protests, promoted by Navalny and his Foundation for Fighting Corruption, (FBK), targeted Prime Minister Dmitry Medvedev, a right-hand man of Putin who served as the nation's president from 2008 to 2012. Navalny accuses Medvedev of amassing yachts, vineyards and country estates through a string of financial schemes and fake companies.

Protesters, some hanging from light polls, shouted slogans, including "Down with Putin!" and "Putin is a thief!"

Navalny tweeted Sunday: "70 billion rubles stolen (by) Medvedev, and now there is a search in the office of FBK. That's why rallies across Russia." The equivalency of 70 billion rubles is more than $1 billion.

The success of the protests comes as vindication of sorts for Navalny, a lawyer and blogger who heads Russia's Progress Party. Last month he was convicted of embezzlement in a highly publicized case that he dismissed as a government-generated sham. He was sentenced to five years in prison. His sentence was suspended, but the conviction could complicate his plans to oppose Putin in the 2018 presidential election.

Putin's popularity has remained strong, in large part because of Russia's show of military strength in Ukraine and Syria. But Medvedev has taken a political hit in recent months, drawing blame for the nation's struggling economy and more recently for the reports of ill-gotten gains, which he has dismissed as propaganda.

The Russian news website RT said local authorities in Moscow had rejected a request from Navalny's legions to march Sunday along Tverskaya Street, the main thoroughfare in Moscow. Two alternative locations proposed by the city were rejected by march organizers.

In St. Petersburg, an unsanctioned opposition rally drew about 3,000 people, according to RT. Three people were detained. A rally in Novosibirsk, which was sanctioned after a court had ordered local authorities to overturn a ban, drew about 1,500 people, RT said. Another sanctioned event in Tomsk attracted about 400 protesters.

Navalny was arrested while walking from the subway to the demonstration, the Associated Press reported.

"Guys, it's okay with me," he tweeted. "You do not have to beat me. Walk along Tverskaya. Our today's topic — the fight against corruption."

Several fracases broke out between protesters and police. One officer suffered a head injury when he was hit by a protester, police said.

“It’s scary, but if everyone is afraid, no one would come out onto the streets,” protester Yana Aksyonova, 19, told the AP.

“People are unhappy with the fact that there’s been no investigation” of the corruption allegations, protester Ivan Gronstein told the wire service.