During the joint German-Soviet invasion of Poland, which started World War II in September 1939, the town was invaded by Nazi Germany, and then the German Einsatzkommando 16 and SS Wachsturmbann "Eimann" entered the town to commit various crimes against Poles. Under German occupation, the town was annexed into the newly formed Regierungsbezirk Danzig in the new province of Reichsgau Danzig-West Prussia. The Polish population was subjected to mass arrests, imprisonment, tortures, massacres, expulsions, deportations to Nazi concentration camps and to forced labour.