Until the last moment before the German attack on the Soviet Union in 1941, cargo trains transported goods from the Soviet Union to Germany. The beginning of German attacks on the Soviet Union on 22 June 1941 resulted in the possession of railway and rolling stock by Ostbahn and the possession of PKP rolling stock with broad gauge track and reconstruction to standard gauge. The beginning of organized sabotage by the Polish resistance movement on railways took place about the same time.