Ruth Elias and her husband had conceived a child while she was a prisoner in the Theresienstadt camp, and when she arrived at Birkenau on a transport of Czech prisoners in December 1943, she was three months pregnant. Ruth passed several selections for the gas chamber even though she was obviously pregnant; she and her husband were assigned to the Czech "family camp." On July 11, 1944, after a selection made by Dr. Mengele, 3,000 prisoners in the Czech family camp, who were not considered fit to work, were sent to the gas chamber, but Ruth passed the selection even though she was in her eighth month of pregnancy. On July 14, 1944, Ruth was sent to Hamburg, Germany to work in clearing rubble from Allied bombing raids.
In May, Nazis under the direction of SS Lt. Colonel Adolf Eichmann boldly began a mass deportation of the last major surviving population of European Jews. From May 15 to July 9, over 430,000 Hungarian Jews were deported to Auschwitz. During this time, Auschwitz recorded its highest-ever daily number of persons killed and cremated at just over 9000. Six huge open pits were used to burn the bodies, as the number of dead exceeded the capacity of the crematories.
Mengele sailed to Argentina in July 1949, assisted by a network of former SS members. He initially lived in and around Buenos Aires, then fled to Paraguay in 1959 and Brazil in 1960, while being sought by West Germany, Israel, and Nazi hunters such as Simon Wiesenthal who wanted to bring him to trial. He eluded capture in spite of extradition requests by the West German government and clandestine operations by the Israeli intelligence agency Mossad. He drowned in 1979 after suffering a stroke while swimming off the Brazilian coast, and was buried under a false name. His remains were disinterred and positively identified by forensic examination in 1985.