At least 260 people have been arrested while protesting against Russian President Vladimir Putin in Moscow, police say.
The protesters are believed to be linked to nationalist politician Vyacheslav Maltsev’s Artillery Preparation movement.
It has been declared extremist and is banned in Russia.
Mr Maltsev says a revolution is imminent. Last year in a debate he called for Mr Putin to be impeached.
He is reported to be living abroad after a Moscow court issued an arrest warrant for him over his calls for extremist measures to overthrow the government.
The Tass news agency quoted police and independent monitors as saying supporters of the radical opposition group convened beside the Kremlin in central Moscow.
Most of the arrests were made in the Russian capital but people were also detained in five other cities.
Some of the protesters in Moscow were reported to be carrying knives, knuckledusters and rubber bullet-firing pistols.
An AFP photographer …