Vladimir Putin the Russian opposition and by international observers from the Organization for Security and Co-operation in Europe for procedural irregularities. Anti-Putin protests took place during and directly after the presidential campaign. The most notorious protest was the Pussy Riot performance on 21 February, and subsequent trial. An estimated 8,000–20,000 protesters gathered in Moscow on 6 May, when eighty people were injured in confrontations with police, and 450 were arrested, with another 120 arrests taking place the following day. A counter-protest of Putin supporters occurred which culminated in a gathering of an estimated 130,000 supporters at the Luzhniki Stadium, Russia's largest stadium.
2014 anti-war protests in Russia dozen activists were arrested outside the Ukrainian Embassy in Moscow for protesting against Russian president Vladimir Putin. Another anti-war rally with about 5,000 to 20,000 demonstrators took place on Pushkinskaya Square in Moscow on 21 September 2014. The "Washington Post" reported that "tens of thousands" protested the war in Ukraine with a peace march in downtown Moscow "under heavy police supervision". There were minor scuffles with pro-Russian supporters, but no serious violence or arrests were reported. About a thousand people also gathered outside the Kazan Cathedral in Saint Petersburg to protest against Russia's involvement in Ukraine. Thousands of people around