Angered over mounting economic problems, thousands of people took to the streets in Moscow and other cities around Russia over the weekend to denounce President Dmitry Medvedev and Prime Minister Vladimir Putin in the largest display of public discontentment in years.

United Russia, the party that dominates Russian politics and is led by Putin, brought thousands of people to Manezh Square near the Kremlin to rally in support of Putin and Medvedev.

The largest anti-government rally took place Saturday in Vladivostok, where the Communist Party led some 2,500 people in a march against the government and a recent decision to increase tariffs on imported cars. The livelihood of many local residents depends on imported cars.

Vladivostok protesters carried banners reading, "Kremlin, we are against you," and some shouted slogans for Putin to resign, news agencies reported.

Vladivostok police kept a close eye on the unauthorized rally but did not intervene. The police violently dispersed a similar protest in December, detaining about 100 people.

In Moscow, about 1,000 Communist demonstrators gathered with signs reading "Putin's plan — Peril to Russia!" at a sanctioned rally on Triumfalnaya Ploshchad, near the Mayakovskaya metro station. Communist leader Gennady Zyuganov called on the government to abandon Western economic models and nationalize broad swathes of the economy.

The 90-minute demonstration was cordoned off by hundreds of OMON riot police, and a helicopter patrolled the sky over central Moscow.

Thomas Peter / Reuters OMON riot police detaining an opposition demonstrator during an anti-government protest in Moscow on Saturday.

Four activists with the banned National Bolshevik Party threw smoke bombs into the crowd, and they were detained quickly by the police.

National Bolshevik leader Eduard Limonov was detained with several supporters as they approached the venue of the Communist demonstration shortly after the Communists left. He was released Sunday after spending the night in detention, a spokesman for Limonov said.

Several hundred people decried the government at two Moscow demonstrations on Sunday.

Also Saturday, several dozen activists with Garry Kasparov's United Civil Front opposition group marched on Bolshaya Polyanka, near the Polyanka metro station, shouting "Down with the government!" and "Russia without Putin!" Young people wearing masks and carrying metal rods brutally beat several protesters while police detained others.

A handful of protesters from the anti-Kremlin youth group My, or "We" in English, rallied outside the White House with blank signs and their mouths taped shut. Police detained all the participants.

A Moscow police spokesman said 41 people — comprising National Bolshevik and United Civil Front activists —were detained briefly Saturday for participating in unauthorized rallies. Over 5,000 officers were deployed.

Yury Maltsev / Reuters Some 2,500 people marching during a Communist-led protest against the government in Vladivostok on Saturday.

The anti-government rallies were largely ignored by state television, which instead covered United Russia's pro-government rallies in Moscow and several other cities. About 9,000 people showed up on Manezh Square for about 30 minutes, waving signs with images of Medvedev and Putin and the words "We trust!" Army soldiers served hot tea and cookies to the participants.

St. Petersburg authorities refused to sanction an opposition rally, so United Civil Front staged one-person pickets in which individuals took turns holding an anti-government poster on the street.

About 500 Communist protesters attended an anti-government rally in Novosibirsk, and some 100 rallied in Sochi, Itar-Tass reported.

The Liberal Democratic Party also held a sanctioned protest in Moscow.

The protests pose a challenge for the government, which saw little public discontent over the past eight years as high oil prices fueled higher living standards. But with oil prices crashing back to earth, the government faces the prospect of growing protests, especially if it is forced to cut social spending, said Alexander Tarasov, a sociologist and Soviet-era dissident. "People's illusions that Russia won't be affected by the global financial crisis have vanished, and the result could easily be wide public indignation," Tarasov said.

Thomas Peter / Reuters An unidentified man attacking an opposition protester Saturday in Moscow.

Alexander Averin, a spokesman for the Other Russia opposition coalition, which includes both National Bolshevik and United Civil Front activists, said the group is planning more protests and expects many more participants by the summer. The opposition, which usually focuses on Moscow and St. Petersburg, will widen its protests to other cities soon, Averin said.

The government is clearly worried about possible unrest. During a meeting with Federal Security Service officers last week, Medvedev stressed that the agency and police force would receive sufficient financial support to keep the situation under control in the country despite the crisis.

"Of course they have fears about our activities," Averin said of the government. "If they weren't afraid, they wouldn't dispatch so many policemen to prevent protests."

Tarasov said he was worried about police violence. "It is also possible that they will try too hard in their attempts to suppress the demonstrators," he said.