MOSCOW — Thousands of protesters rallied across Russia today to criticize the government's economic course and its response to the global financial crisis.

The protests, among the strongest yet, reflected simmering public anger over economic conditions and posed a challenge to the Kremlin, which had faced little threat from the fragmented opposition and politically apathetic population during the years of oil-driven boom.

About 2,500 people marched across the far eastern port of Vladivostok to denounce the Cabinet's decision to increase car import tariffs, and some shouted slogans urging Prime Minister Vladimir Putin to resign.

Many in the region make their living from importing cars.

In Moscow, about 1,000 Communist demonstrators rallied on a central square surrounded by heavy police cordons.

There, Communist Party chief Gennady Zyuganov said the government must abandon Western economic models and conduct broad nationalization.

Eduard Limonov, leader of the banned National Bolshevik Party, was detained by police at another Moscow square. Limonov is one of the most radical critics of the Kremlin.

Demonstrators from chess star Garry Kasparov's United Civil Front opposition group caught police by surprise when they started an unsanctioned rally on a street near the Kremlin. Kasparov did not take part in the protest.