Holocaust Researchers Catalog 42,500 Nazi Ghettos, Camps; Numbers Are 'Unbelievable'

They've identified more than 42,500 of various sizes, about six times the number they expected to find. The sites ranged from killing centers to brothels to ghettos to labor camps.
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The lead editors of a multi-volume encyclopedia being published by the museum put the number of people imprisoned or killed at the sites at 15 million to 20 million.

Source: http://www.newser.com/story/163726/holocaust-even-worse-than-we-thought.html