To kill Jews more quickly, the Nazis constructed large gas chambers at the extermination camps. Jews selected for extermination were ordered to leave behind their belongings and strip off all their clothes, ostensibly for a delousing shower. Hundreds of naked people were then crowded into the gas chamber. Instead of water, however, the Nazis sealed the chamber and poured in poison gas. Within a matter of minutes, all of the Jews in the gas chamber were dead.