'Friendly Concentration Camp': Russian Critic Navalny Describes Tight Control at This Moscow Prison; See Pics

Prison colony IK-2, which stands out among Russian penitentiary facilities for its particularly strict regime, is seen in Pokrov in the Vladimir region, 85 kilometers (53 miles) east of Moscow, Russia, on Feb. 28, 2021. Russian opposition leader Alexei Navalny described tight controls at his prison in a letter posted Monday, March 15, 2021, saying they include hourly checks during the night. Navalny said that he hasn't seen even a hint at violence" there but faced overwhelming controls that he compared to George Orwell's "Nineteen Eighty-Four." (AP Photo/Kirill Zarubin)

Prison colony IK-2 is seen in Pokrov in the Vladimir region, 85 kilometers (53 miles) east of Moscow, Russia, on Feb. 28, 2021. Navalny's note posted on his Instagram page confirmed for the first time that he arrived at a prison colony in Pokrov in the Vladimir region, 85 kilometers (53 miles) east of Moscow, which stands out among Russian penitentiary facilities for its particularly strict regime. (AP Photo/Kirill Zarubin)

Prison colony IK-2 is seen in Pokrov in the Vladimir region, 85 kilometers (53 miles) east of Moscow, Russia, on Feb. 28, 2021. Navalny, 44, Russian President Vladimir Putin’s most vociferous foe, was arrested on Jan. 17 upon returning from Germany, where he spent five months recovering from a nerve-agent poisoning that he blames on the Kremlin. Russian authorities have rejected the accusation. (AP Photo/Kirill Zarubin)

FILE - In this Saturday, Feb. 20, 2021 file photo, Russian opposition leader Alexei Navalny stands in a cage in the Babuskinsky District Court in Moscow, Russia. Navalny described the prison, IK-2, as a “friendly concentration camp.” In a letter posted Monday March 15, 2021, he said they include hourly checks during the night. (AP Photo/Alexander Zemlianichenko, File)

A view shows a window at the Detention centre number 3 (SIZO-3), where opposition leader Alexei Navalny, who was sentenced on parole violations, was supposedly being held, in the town of Kolchugino in Vladimir Region, Russia March 4, 2021. (REUTERS/Evgenia Novozhenina)

A view shows the Detention centre number 3 (SIZO-3), where opposition leader Alexei Navalny was reported to being held, in the town of Kolchugino in Vladimir Region, Russia March 4, 2021. (REUTERS/Evgenia Novozhenina)

A view shows the Detention centre number 3 (SIZO-3), where opposition leader Alexei Navalny, who was sentenced on parole violations, is supposedly being held, in the town of Kolchugino in Vladimir Region, Russia March 4, 2021. (REUTERS/Evgenia Novozhenina)

A view shows the Detention centre number 3 (SIZO-3), where opposition leader Alexei Navalny, who was sentenced on parole violations, is supposedly being held, in the town of Kolchugino in Vladimir Region, Russia March 4, 2021. (REUTERS/Evgenia Novozhenina)