Police detained more than 2,000 people at anti-war protests in 48 cities across Russia on Sunday, a protest monitoring group said, as people defied authorities to show their anger over Russia's invasion of Ukraine.
Since the invasion began Thursday, more than 5,500 people have been detained at various anti-war protests, according to the OVD-Info monitor, which has documented crackdowns on Russia's opposition for years.
In Moscow, riot police often outnumbered protesters, some carrying handwritten placards with peace signs and anti-war slogans in Russian and Ukrainian. Some wore masks with the word "Enough" on the front.
A reporter for the independent television channel Dozhd was arrested during the protests despite showing his accreditation to police and wearing a press vest.
Outside the upmarket Gostiny Dvor department store in downtown Saint Petersburg, hundreds of anti-war protesters stood together, linking arms and chanting.
Sunday's protests coincided with the seventh anniversary of the murder of opposition politician Boris Nemtsov.
In Moscow, some of the arrests took place at an improvised memorial just outside the Kremlin at the site where Nemtsov was shot, a Reuters witness said.
"No to war," shouted one of the demonstrators as he was being dragged away by the police.
Nemtsov was a prominent critic of President Vladimir Putin, Russia's annexation of Crimea in 2014 and Moscow's support for pro-Russian separatists in Ukraine that ultimately led to what Putin labels a "special operation" to protect the two separatist regions although his troops are fighting in wider Ukraine.
Ukraine's Western allies have slapped unprecedented sanctions in response to Russia's land, sea and air invasion.
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Tens of thousands of people across Europe marched against Russia's invasion on Sunday, with 100,000 protesting in Berlin, in solidarity with Ukraine.