Genocide is the deliberate, systematic killing of an entire people, nation, ethnic group, or other distinct group of people, with the intent to destroy the group in whole or in part. It is considered the most extreme form of intergroup intolerance and a grave violation of human rights. Genocide can involve various methods of extermination, including mass killings, forced displacement leading to death, the imposition of measures intended to prevent births within the group, and the forcible transfer of children of the group to another group. The Holocaust, in which Nazi Germany systematically murdered approximately six million Jews, is a well-known historical example of genocide. Other instances include the treatment of aboriginal Australians by white settlers and the European colonisation of North America, which led to a drastic decline in Native American populations, partly due to the introduction of European diseases. The ongoing conflict in the Darfur region of Sudan has also been cited as a contemporary example of genocide. The prevention and punishment of genocide are major concerns of international law and human rights efforts.