EN
The paper is devoted to the activities of police intelligence branch in Košice in the former Czechoslovakia in the interwar period (1918-1939). The research is based mainly on the rich archival fund of the Police Intelligence Service in Košice. The protection of army and military issues of the state represents a limited but significant part of the activities of the Police Intelligence Service. The study is dealing with the theme of the state of scientific research about the intelligence services in interwar Czechoslovakia; the creation of the Police Intelligence Branch in Košice; the cooperation and conflicts of jurisdiction with the other security authorities in the state; the problematic issues and specific cases of espionage of the Czechoslovak army and national defence.