<p>Jews from the Lodz ghetto are loaded onto freight trains for deportation to the Chelmno killing center. Lodz, Poland, 1942–44.</p>

Killing Centers: An Overview

The Nazis established killing centers in German-occupied Europe during World War II. They built these killing centers exclusively or primarily for the mass murder of human beings. Nazi officials employed assembly-line methods of murder in these facilities.

Key Facts

  • 1

    Nazi officials deployed the first killing centers at T4 (“euthanasia”) facilities to murder institutionalized persons with disabilities between 1940 and 1941.

  • 2

    Chelmno, the first killing center for the mass murder of Jews, was established in December 1941. In 1942, Belzec, Sobibor, and Treblinka were established as a part of Operation Reinhard with the goal of murdering all the Jews of the General Government.

  • 3

    More than 1.1 million people were killed in the Auschwitz-Birkenau labor camp and killing center. Of those, nearly one million were Jews. Those Jews who were not sent directly to the gas chambers were deployed in forced labor.

Killing CentersThe Nazis established killing centers for efficient mass murder. Unlike Nazi concentration camps, which served primarily as detention and labor centers, killing centers (also referred to as “extermination camps” or “death camps”) were almost exclusively “death factories.” At these killing centers, Nazi officials employed assembly-line methods to murder Jews and other victims. German SS (Schutzstaffel; Protection Squadrons) and police murdered nearly 2,700,000 Jews in the killing centers either by asphyxiation with poisonous gas or by shooting.

Operation T4: The Euthanasia Program 

Killing centers first made their appearance in Nazi Germany with Operation T4, the so-called euthanasia program. The Euthanasia Program was the systematic murder of institutionalized patients with disabilities in Germany. From January 1940 through late August 1941, some 70,273 adult patients were murdered in gas chambers using chemically pure carbon monoxide gas.

Chelmno, Belzec, Sobibor, and Treblinka

To carry out the "Final Solution" (the genocide or mass murder of Jews), the Nazis established killing centers in German-annexed and occupied Poland. 

Established in December 1941, Chelmno was the first killing center for the mass murder of Jews. It was located in the Warthegau, the western part of prewar Poland annexed by Germany during World War II. Mostly Jews, but also Roma (Gypsies), were gassed in mobile gas vans at the Chelmno killing center. 

In 1942, Nazi officials established the Belzec, Sobibor, and Treblinka killing centers in the General Government. These killing centers were part of Operation Reinhard, the German plan to systematically murder the remaining Jews in German-occupied Poland. In the Operation Reinhard killing centers, the SS and their auxiliaries killed approximately 1,526,500 Jews between March 1942 and November 1943. The overwhelming majority of those who arrived at these camps were immediately murdered in gas chambers. 

At the Chelmno and Operation Reinhard camps, victims were murdered using carbon monoxide produced by diesel exhaust.


Selection of Hungarian Jews at the Auschwitz-Birkenau killing center.The largest killing center was Auschwitz-Birkenau, which by spring 1943 had four gas chambers in operation. Since the Auschwitz main camp (Auschwitz I) was a labor camp, Jewish prisoners arriving at the Auschwitz complex faced a selection process. Those judged best able to work were selected for labor, while the majority of the transport were sent immediately to death in the gas chambers. At the height of the deportations, an average of 6,000 Jews were gassed each day at the Auschwitz II (Birkenau) killing center using Zyklon B, a poisonous gas. By November 1944, over a million Jews and tens of thousands of Roma, Poles, and Soviet prisoners of war were killed there.


Many scholars have traditionally counted the Majdanek camp, which was located just outside the city Lublin, as a sixth killing center. However, recent research has shed more light on the functions and operations at Lublin-Majdanek. 

Within the framework of Operation Reinhard, Majdanek primarily served as a place to concentrate Jews whom the Germans spared temporarily for forced labor. It occasionally functioned as a killing site to murder victims who could not be killed at the Operation Reinhard killing centers, namely at Belzec, Sobibor, or Treblinka. The Majdanek camp also included a storage depot for property and valuables taken from the Jewish victims at the killing centers.

Disguising Mass Murder

The SS considered the killing centers top secret. To obliterate all traces of gassing operations, Sonderkommandos or special prisoner units were forced to remove corpses from the gas chambers and cremate them. The grounds of some killing centers were landscaped or camouflaged to disguise the murder of millions. Moreover, the Special Action 1005 (Sonderaktion 1005), begun in May 1942, deployed prisoners to exhume and burn bodies from mass graves where cremation was not practiced.

Discussion Questions

Critical Thinking Questions

  • What resources and personnel were needed to plan, construct, and operate a killing center?
  • Investigate how secret the use of killing centers was during the Holocaust. How and when did the outside world learn about these operations?

Further Reading

Arad, Yitzhak. Belzec, Sobibor, Treblinka: The Operation Reinhard Death Camps. Bloomington: Indiana University Press, 1987.

Berenbaum, Michael, and Yisrael Gutman, editors. Anatomy of the Auschwitz Death Camp. Bloomington: Indiana University Press, in association with the United States Holocaust Memorial Museum, 1998.

Chrostowski, Witold. Extermination Camp Treblinka. London: Vallentine Mitchell, 2004.

Delin, Grant. Lebensraum: Extermination Camps of the Third Reich. London: Westzone Publishing, 2001.

Hilberg, Raul. The Destruction of the European Jews. New Haven, CT: Yale University Press, 2003.

Levi, Primo. Survival in Auschwitz. Trans. Stuart Woolf. New York: Simon & Schuster, 1996.

Mendelsohn, John, editor. The "Final Solution" in the Extermination Camps and the Aftermath. New York: Garland Publishing, 1982.

Schelvis, Jules, and Bob Moore. Sobibor: A History of a Nazi Death Camp. Oxford: Berg, 2007.

Wiesel, Elie. Night. Trans. Marion Wiesel. New York: Hill and Wang, 2006.

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