On 27 January 1945, Auschwitz—a Nazi concentration camp and extermination camp in occupied Poland where more than a million people were murdered as part of the Nazis' "Final Solution" to the Jewish question—was liberated by the Soviet Red Army during the Vistula–Oder Offensive. Although most of the prisoners had been forced onto a death march, about 7,000 had been left behind. The Soviet soldiers attempted to help the survivors and were shocked at the scale of Nazi crimes. The date is recognized as International Holocaust Remembrance Day.