The Nazis killed many groups of people they selected, known as "The Holocaust". They exterminated Jews, and killed the Roma, , , homosexuals and other groups. Around 11 to 17 million civilians died. Around 7.5 million people were killed in China by the Japanese. The most well-known Japanese crime is the Nanking Massacre, in which hundreds of thousands of Chinese civilians were raped and murdered. There were reports that the Germans and Japanese tested biological weapons against civilians and prisoners of war.