Russian police have detained opposition leader Alexei Navalny at a demonstration against President Vladimir Putin in central Moscow.
Thousands of demonstrators denouncing Mr Putin's upcoming inauguration into a fourth term gathered in the capital's Pushkin Square.
Video showed police carrying a struggling Mr Navalny, who is Mr Putin's most prominent foe, out of the square, carrying him by the legs and arms.
The unauthorised protest was part of a day of nationwide demonstrations under the slogan "He is not our tsar."
Police made arrests at demonstrations in some other cities, but there was no overall figure immediately available.
