On 8 May 1945 a State commission compiled by the Soviets with advice from Polish, French and Czechoslovak experts revealed the full horror of conditions at the camp. Nearly 3,000 survivors of various nationalities were questioned and on the basis of their evidence the report estimated 4,000,000 people had perished there between 1941 and early 1945. The dead included citizens from the Soviet Union, Poland, France, Belgium, Holland, Czechoslovakia, Yugoslavia, Hungary, Italy and Greece.
The commission, which had previously investigated conditions at Majdanek, Treblinka and other camps, described Auschwitz as the worst in its experience. It found evidence of experiments carried out on humans "of a revolting character". According to the evidence, the commission said the Germans had moved out up to 60,000 inmates - those still fit enough to walk - when they retreated.
The few thousand who were left behind were freed by the Russians. They also found seven tons of women's hair, human teeth, from which gold fillings had been extracted and tens of thousands of children's outfits. The final death toll was later revised downwards to between 1 and 1.5 million, including 800,000 Jews.
Taken from http://news.bbc.co.uk/onthisday/hi/dates/stories/january/27/newsid_3520000/3520986.stm
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