Some railways could not be used at night or on some days, and trains were forced to travel at a slower speed.[3] There were more than 300 partisan attacks on rail communications from Summer 1944 to May 1945.[4] Waffen-SS units retreating from the Red Army's advance into Moravia burned down entire villages as a reprisal.[5] Partisan groups had a diverse membership including former members of Czech resistance groups fleeing arrest, escaped POWs, and German deserters.[6] Other partisans were Czechs who lived in rural areas and continued with their jobs during the day, joining the partisans for night raids.[7]