TOPSHOT - Russian police officers guard the entrance to the penal colony N2, where Kremlin critic Alexei Navalny has been transferred to serve a two-and-a-half year prison term for violating parole, in the town of Pokrov on April 6, 2021. - The Alliance of Doctors medical trade union said it would organise a protest outside the penal colony in Pokrov on Tuesday, demanding Navalny receive adequate medical treatment. (Photo by Kirill KUDRYAVTSEV / AFP)