MOSCOW (Reuters) - Russian detectives said on Friday they had new evidence in the investigation into an outspoken Kremlin opponent and his associates who allegedly sought to stir mass disorder and overthrow President Vladimir Putin's government.
The federal Investigative Committee, a state body with extended powers, formally charged leftist opposition leader Sergei Udaltsov and two associates last month with organizing mass disorder and detained them ahead of trial.
The men deny the charges and say they are victims of Putin's crackdown on the opposition following mass protests against his 13-year rule.
Udaltsov has since been released but faces a sentence of up to 10 years if convicted. His two associates remain in detention.
The charges against them were based on hidden-camera footage broadcast by a pro-Kremlin channel that it said showed Udaltsov and his two associates conspiring with a Georgian politician to organize mass riots.
"Since then the investigation has moved further," the Committee said in a statement.
It said it had obtained evidence that Udaltsov and the two other men were conspiring with the "foreign citizens".
The Committee said it also has witness testimonies confirming the intentions of the group as well as information that Udaltsov's supporters had been abroad for training on how to ferment unrest.
Putin has signed laws increasing fines for violations at street demonstrations and tightening controls on foreign-funded, non-governmental organizations that Russia accuses of meddling in its domestic politics.
(Reporting by Gleb Bryanski; Editing by Sophie Hares)