Police officers detain Alexei Navalny, center, on his way to attend a rally in Manezhnaya Square in Moscow. (Associated Press)
Police have detained President Vladimir Putin's chief foe, who has broken the terms of his house arrest to attend a protest of several thousand just outside the Kremlin.
The unsanctioned demonstration on Tuesday came hours after Alexei Navalny, the anti-corruption campaigner, was found guilty of fraud and given a suspended sentence of three and half years. His brother was sent to prison.
The convictions are widely seen as a political vendetta against any opposition to Putin and his government.
Alexei Navalny, who has been under house arrest since February, broke its terms to attend the rally and was rounded up by police as he approached the site of the protest.