With what? I am assuming you know the rest of the story. We won the war. Allied soldiers rescued the few remaining dying people in the concentration camps. When they were losing the war they knew there would be inquisitions.  So to cover their tracks they had the inmates undig the bodies and burn them in open fires to try to destroy as much evidence as they could. There was an inquisition it was called the Nuremberg trials, in case you didn't hear.