WARSAW – Poland has reopened investigations into crimes committed at the Nazi death camp of Auschwitz during World War Two, in an effort to track down any surviving camp employees before they die. Up to 1.5 million people, mostly Jews, perished at Nazi German hands at Auschwitz, near the city of Krakow in southern Poland, during the war that ended in 1945. In the postwar communist era, Warsaw launched probes into crimes committed at Auschwitz, but closed them in the 1980s because questioning witnesses and perpetrators based abroad was too hard at a time when Poland was part of the Soviet bloc.