Russian art teacher Daniil Klyuka, 28, was arrested in February 2023 by masked members of Russia's feared FSB security service -- he believes the headmistress of the provincial school where he worked reported him for doodling horns on pictures of officials in a newspaper. Sentenced to 20 years in jail -- accused of sending money to an ultranationalist Ukrainian brigade, which he denies -- Klyuka's case illustrates the severity of the crackdown on dissent, both real and imagined, in Russia since the invasion of Ukraine. AFP was able to reconstruct his descent into the depths of the Russian penal system through letters he exchanged with a Russian anti-war activist living in exile in Italy, Antonina Polishchuk, who decided to come to his aid. IMAGES AND SOUNDBITES