- Killing centers are also known as concentration camps or "death camps".
- The German killed about 2,700,000 Jews in the killing centers by poison gas or by shooting.
- The first killing center was Chelmno, in Warthegau, and there were many Jews were killed by poison gas. In 1942, the Nazis opened Belzec, Sobibor, and Treblinka killing centers in the Generalgouvernement.
- Treblinka killing centers mostly know as Operation Reinhard camps.
- About 1,526,500 Jews were killed between March 1942 and November 1943, at Operation Reinhard camps .
- The largest killing center is Auschwitz-Birkenau.
- The Nazis keep the killing centers as top secret , so people don’t know how they use poison gas to kill Jews.
- When the Jews die the Nazis burn their bodies.