A report by a former inmate of Auschwitz who was assigned to construction work at the Buna IG-Farben plant, while the majority of his transport - like that of all other transports - were sent immediately after arrival at Auschwitz from the Todesrampe to the gas chambers of Birkenau. By March 1943 the number of slave workers had grown to 15,000. New transports arrived every week to replace those sent as unfit for work to the gas chambers or who were killed by the guards or by hunger, exhaustion or epidemics. The worst selection for the gas chamber occurred at the end of winter 1943 when the camp commander, Obersturmführer Schwarz sent almost half of the inmates of Buna to the gas chambers. Production in the plant started at the beginning of 1944. Representatives and overseers of the IG-Farben forced the prisoners to increase their speed of work and reported every instance of “slacking” to the SS. Some political prisoners started a resistance movement and, by killing some of the most brutal kapos, succeeded in somewhat improving the conditions. On 18 January 1945, when the Russians approached the camp, the SS drove the prisoners out of the camp; many of them died on the death march to the West.

The author of the report estimates that 150,000 people died in the camp as the result of beatings, hunger and epidemics (without counting those sent for gassing to Birkenau).