Anti-Vladimir Putin protests erupted across Russia as supporters of opposition leader Alexei Navalny demanded his release from prison.
The wave of demonstrations happened as Putin celebrated his 65th birthday while Navalny served a 20-day jail term for calling for an earlier unsanctioned protest.
A rally in Putin’s hometown of St Petersburg Violent ended in violent clashes with police.
Several hundred protesters, most of them students, waved Russian flags and chanted “Russia will be free!” and “Let Navalny run!”.
Police warned them the rally wasn’t sanctioned and urged them to disperse, but let the protest continue for hours without trying to break it up.
More than 1,000 people gathered at Marsovo Pole park and marched across the city, cutting traffic and chanting “Russia without Putin!” and “Putin, retire!”
Police later cracked down on the demonstrators, detaining dozens after some tried to break through police lines.
Protestor Dmitry Samokhin, 18, said: “Putin has been in charge since I was born. The country is mired in stagnation and I want to see changes.”
Navalny’s headquarters called protests in 80 cities. Most were not sanctioned by authorities, but police largely refrained from breaking them up.
The Siberian city of Yakutsk saw the toughest police response, where a few dozen demonstrators were reportedly detained.
Navalny has declared his intention to run for president in the March 2018 election, even though a criminal conviction that he calls politically motivated bars him from running.
The 41-year-old anti-corruption leader has organised waves of protests this year in challenge to the Kremlin.
Putin has not yet announced whether he would seek re-election, but he is widely expected to run.
Navalny argues that the high level of support for Putin – currently estimated at over 80% – comes from the lack of real political competition and urged supporters to help him get registered.