The consequence of the absence of any overt documentary evidence of gas chambers at these camps, coupled with the lack of archaeological evidence, means that reliance has to be placed on eye witness and circumstantial evidence. 2
As the German army was pushed back, the places we had called concentration camps were opened up. When the first reports came through, they were not believed. People have long memories for some things. During the First World war there had been atrocities stories of bodies boiled down for glycerine, babies tossed onto bayonets, which were afterwards discredited as mere hate propaganda. But this time there were eye-witness accounts from soldiers and war correspondents who entered the camps and saw what they contained. Delegations of politicians, lawyers, doctors, were sent to verify these reports. I was appointed to such a mission, by the French government. ...
Belsen came first: the furances used for burning corpses were still smoking. To enter the camp area we had to wear gas masks, protective clothing and gloves. Once inside, all we could do was wander among the half dead, murmuring useless words, trying to avoid the eyes of men and women who were not much more than skeletons in rags.
I was shown the files in the administration section, the bills and receipts, neatly typed and rubber stamped, "We beg to acknowledge delivery of your improved gas chambers. We have found them most efficient." 4
4. De Rothschild, Littlewood, Candid Autobiography, pp.212-213.