The town's synagogue was burned in 1938 during the "Kristallnacht" pogrom carried out against Jewish population. In 1944, Boeing B-17 Flying Fortresses of the USAAF bombed the gas works at Bielefeld on September 20 and the marshaling yard on September 30; Bielefeld was bombed again on October 7 and the RAF bombed the town on the night of December 4/5. On January 17 1945 B-17s bombed the nearby Paderborn marshalling yard, and the railway viaduct in the suburb of Schildesche. On March 14 the RAF bombed the viaduct again, wrecking it. This was the first use of the RAF's 10 tonne Grand Slam bomb. American troops entered the city in April 1945.