current estimates put the number of prisoners who passed through the concentration camp during its period of operation from 1943 to 1945 at around 120,000. due to the destruction of the camp's files by the ss, not even half of them, around 55,000, are known by name. as mentioned above, treatment of prisoners by the ss varied between individual sections of the camp, with the inmates of the exchange camp generally being better treated than other prisoners, at least initially. however, in october 1943 the ss selected 1,800 men and women from the "sonderlager" ("special camp"), jews from poland who held passports from latin american countries. since the governments of these nations mostly refused to honour the passports, these people had lost their value to the regime. under the pretext of sending them to a fictitious "lager bergau", the ss had them transported to auschwitz-birkenau, where they were sent directly to the gas chambers and killed. in february and may 1944 another 350 prisoners from the "special camp" were sent to auschwitz. thus, out of the total of 14,600 prisoners in the exchange camp, at least 3,550 died, more than 1,400 of them at belsen, and around 2,150 at auschwitz.