Alleged from April '43 to October '44 at each of the 2 cremation buildings: An average 1,000 a day in small groups walked into a below-ground-level undressing room, and then into an adjoining room where cyanide gas pellets were dropped through 4 roof-vents which killed the screaming victims within 15 minutes. After 20 minutes the one door was opened and workers lifted the bodies upstairs to be quickly cremated. Place your cursor over a number.