The Holocaust (from the Greek ὁλόκαυστον (holókauston): holos, "completely" and kaustos, "burnt"), also known as Ha-Shoah (Hebrew: השואה), Churben (Yiddish: חורבן), is the term generally used to describe the killing of approximately six million European Jews during World War II, as part of a program of deliberate extermination planned and executed by the National Socialist (Nazi) regime in Germany led by Adolf Hitler.[2] Other groups were persecuted and killed by the regime, including the Roma; Soviets, particularly prisoners of war; ethnic Poles; other Slavic people; the disabled; gay men; and political and religious dissidents, such as Jehovah's witnesses.[3][4] Many scholars do not include these groups in the definition of the Holocaust, defining it as the genocide of the Jews,[5] or what the Nazis called the "Final Solution of the Jewish Question." Taking into account all the victims of Nazi persecution, the death toll rises considerably: Donald Niewyk suggests that the broadest definition, including Soviet civilian deaths, would produce a death toll of 17 million.[6] The persecution and genocide were accomplished in stages. Legislation to remove the Jews from civil society was enacted years before the outbreak of World War II. Concentration camps were established in which inmates were used as slave labour until they died of exhaustion or disease. Where the Third Reich conquered new territory in eastern Europe, specialized units called Einsatzgruppen murdered Jews and political opponents in mass shootings. Jews and Roma were crammed into ghettos before being transported hundreds of miles by freight train to extermination camps where, if they survived the journey, the majority of them were killed in gas chambers. Every arm of Germany's bureaucracy was involved in the logistics of the mass murder, turning the country into what one Holocaust scholar has called "a genocidal state."