Aurelio Fernández Sánchez joined the National Confederation of Labor (Spanish: Confederación Nacional del Trabajo CNT) in his youth.
[1] In July 1936, after the outbreak of the Spanish Civil War, he joined the Central Committee of Antifascist Militias of Catalonia (CCMA) as a representative of the FAI,[2] assuming direction of the Research Department.[n.
2] When the CCMA was replaced by the new Internal Security Board, Fernández continued as head of the control patrols when he was appointed general secretary of the new body.
Fernández fiercely resisted the new security delegate, a part of the republican state's police force, but was eventually imprisoned.
[8] A major investigation was then launched into the murders and robberies committed between July 1936 and May 1937: Aurelio Fernández was prosecuted for fraud and extortion.