The camp commandant, one Martin Weiss, had hurriedly left well before the Americans arrived with most of his staff. He had placed the camp in charge of SS-Obersturmführer (lieutenant) Skodzensky with orders to surrender as soon as the Americans arrived. Senior Nazis were concerned that prisoners, some of them common criminals and many communists, would escape and try to take revenge by terrorizing local German civilians. It was extemely unusual for such a large camp to be placed in charge of such a low ranking officer, but desparate times were at hand.
Dachau was not set up as a death camp as such although many prisoners died there. In addition to being a prison camp, Dachau was also both a training centre for Waffen SS troops as well as a hospital for wounded SS troops wounded on the eastern front. Unfortunately, for the Waffen SS troops, to get into the camp proper, one had to go through their designated area. American soldiers liberating the camp were not apt to distinguish between Waffen SS and those SS units that looked after running the camps.
What the US soldiers saw at Dachau horrified them to such a degree that simply lost control and reportedly killed over 500 SS men in cold blood, including the commanding officer, after they had surrended. About 40 were shot in the legs and then left to be finished off by former prisoners with shovels or clubs. Wounded SS soldiers, mostly from the eastern front, were dragged from their hospital beds and dealt with in the same manner.
Subsequently the US army investigated and charges were laid. When General George S. Patton learned of this he requested that all documents be immediately forwarded to his office. He placed all this material into a metal waste container and personally set fire to it. It was not until 1991 that the US army quietly declassified the previously secret report of what had happened.
With each passing decade, especially since the collapse of the evil empire which opened up previously closed archives, it has become evident that the Soviets were even worse than the Nazis in their inhumanity.