Witnesses said at least 100 people were detained by police
Russian riot police have forcibly broken up a rally being held in the eastern city of Vladivostok.
About 500 people had gathered in the city's central square to demonstrate against a new tax on imported cars.
Witnesses said police officers kicked protesters, damaged journalists' equipment and made dozens of arrests.
Vladivostok, one of several cities holding protests, depends heavily on car imports from Japan and critics say the tax could push prices up by 50%.
The tax is intended to help prop up Russia's domestic car industry and prevent people buying cheaper, imported products.
Protests against it began a week ago and have also been held in at least nine other cities in far eastern Russia, local Russian media report.
Most of the demonstrations were dispersed by police, said the independent Russian radio station Ekho Moskvy.
More are planned for Moscow and other cities.
Witnesses said the several hundred people who had gathered in central Vladivostok were singing and dancing but that the rally was peaceful with no sign of political placards.
Some protesters are dragged away by riot police
Some of the protesters were reported to have been shouting slogans against the Prime Minister, Vladimir Putin.
The protesters were ordered to disperse by police who told them the rally was unauthorised, before members of the Omon riot police began to arrest people, hauling them into waiting vans, said witnesses.
Several journalists were detained and there were reports that others were injured or had their cameras and recording equipment damaged by the police.
"They ran into the crowd, grabbed people and started pushing them to the ground, taking them into cars," protester Yevgeniy Makarov told Russian media.
"If someone started struggling ... they started twisting their arms, kicking them in the back. Very many people were taken into vans, just thrown there."
A 62-year-old woman who saw the incident said the police were also arresting passers-by.
"They started taking people away without any sort of comment," she said.
The BBC's Richard Galpin in Moscow says protests against the new tax have been fuelled by the severe impact of the global economic crisis on Russia.
The country's industrial output dropped 10.8% during November and its reliance on raw material exports means it has been been hit by falling oil prices and a reduction in demand.
But such open displays of anger are an unusual sight in Russia, where the government keeps tight control of the public and the media, says our correspondent.
This page is best viewed in an up-to-date web browser with style sheets (CSS) enabled. While you will be able to view the content of this page in your current browser, you will not be able to get the full visual experience. Please consider upgrading your browser software or enabling style sheets (CSS) if you are able to do so.