Members of the National Bolshevik Party waved red flags and shouted antigovernment slogans from the Finance Ministry windows before the police arrived.
Party spokesman Aleksandr Averin told RFE/RL's Russian Service the protest was over the Kremlin's decision this year to pay back Russia's Soviet-era foreign debt early, rather than compensate Russians who lost money due to the shock economic reforms of the early 1990s.
Averin put the number of demonstrators who entered the building at 50, and said they had "seized three floors of the building" in the 30 minutes before they were detained.
Witnesses said the protesters, some of whom had climbed onto window sills, offered no resistance to arrest.
RFE/RL Russia Report
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