Russians in dozens of cities across the country have staged anti-war demonstrations, following a call by advisers close to jailed opposition leader Alexei Navalny.As of Sunday, the independent OVD-Info monitoring group reports over 4,500 were detained across 63 cities, with more than 2,100 in Moscow and more than 1,100 in St. Petersburg."The screws are being fully tightened — essentially we are witnessing military censorship," Maria Kuznetsova, OVD-Info's spokesperson, told Reuters.Since protests against Russia's invasion of Ukraine began on Feb. 24, nearly 13,000 people have been detained across Russia, according to the group.Given the number of protests, there was a heavy presence of special police forces patrolling near the Kremlin on Sunday, with Red Square sealed off. A similar scene played out near Palace Square in St. Petersburg — which has seen repeated crowds protest the war. Copyright 2022 NPR. To see more, visit https://www.npr.org.