Ghettos were intended to be temporary until the Jews were deported to other locations, which never happened. Instead, the inhabitants were sent to extermination camps. The ghettos were, in effect, immensely crowded prisons serving as instruments of "slow, passive murder." Though the Warsaw Ghetto contained 30% of Warsaw's population, it occupied only 2.5% of the city's area, averaging over 9 people per room. Between 1940 and 1942, starvation and disease, especially typhoid, killed many in the ghettos. Over 43,000 Warsaw ghetto residents, or one in ten of the total population, died in 1941; in Theresienstadt, more than half the residents died in 1942.
Josef Mengele (/ˈmɛŋɡələ/; German: [ˈmɛŋələ]; 16 March 1911 – 7 February 1979) was a German Schutzstaffel (SS) officer and physician in Auschwitz concentration camp during World War II. He performed deadly human experiments on prisoners and was a member of the team of doctors who selected victims to be killed in the gas chambers. Arrivals that were judged able to work were admitted into the camp, while those deemed unsuitable for labor were sent to the gas chambers to be killed. With Red Army troops sweeping through Poland, Mengele was transferred 280 kilometers (170 mi) from Auschwitz to the Gross-Rosen concentration camp on 17 January 1945, just ten days before the arrival of the Soviet forces at Auschwitz. After the war, he fled to South America where he evaded capture for the rest of his life.