The Jews most apprehensive of danger were brutally beaten to speed up the process. At times, the new arrivals who had suitable skills were selected to join the "Sonderkommando". Once in the changing area, the men and boys were separated from the women and children and everyone was ordered to disrobe for a communal bath: "quickly – they were told – or the water will get cold". The old and sick, or slow, prisoners were taken to a fake infirmary named the "Lazarett", that had a large mass grave behind it. They were killed by a bullet in the neck, while the rest were being forced into the gas chambers.