Nagy and his unit were later encircled and he was ultimately taken prisoner by the Czechoslovak Legion in early September 1918. He escaped captivity and spent the period until February 1920 holding odd jobs in White-controlled territory near Lake Baikal. The Red Army reached Irkutsk on 7 February 1920, ending Nagy's participation in the Civil War. On 12 February 1920 he became a candidate member of the Russian Communist Party and a full-time member on 10 May. He served the rest of 1920 as a clerk for the communist Cheka secret police on matters related to prisoners of war.
Nagy and his unit were later encircled and he was ultimately taken prisoner by the Czechoslovak Legion in early September 1918 He escaped captivity and spent the period until February 1920 holding odd jobs in White-controlled territory near Lake Baikal The Red Army reached Irkutsk on 7 February 1920 ending Nagy's participation in the Civil War On 12 February 1920 he became a candidate member of the Russian Communist Party and a full-time member on 10 May He served the rest of 1920 as a clerk for the communist Cheka secret police on matters related to prisoners of war