As the tensions between Czechoslovakia, local Germans and Nazi Germany grew, the guard was deployed on the border during May 1938 and stayed there until end of September, when Sudetenland was ceded to Germany. During September the guard fought low-level warfare against local German partisans ("Sudetendeutsches Freikorps") and commandos from Germany. After the loss of borderland, SOS moved inland to new positions. The clashes had still occurred but on smaller level.