In 1939, frequent border violations by Germany took place, and on 25 August, Germany halted international rail transport. On 1 September 1939, the day of the German invasion of Poland, which marked the beginning of World War II, at dawn, the Germans invaded the town, which was recaptured by the Poles in the morning, however, it soon fell to Germany. During the German occupation, the Polish population was subjected to various crimes, and in December 1939 the Germans expelled 110 Poles, activists, officials and wealthier residents with entire families, whose homes were then handed over to German colonists as part of the "Lebensraum" policy. The Germans operated a Nazi prison and a forced labour camp for Jews in the town, and destroyed the pre-war monument dedicated to the Polish insurgents of the Greater Poland uprising of 1918–1919.