<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

In German-occupied Europe during World War II, killing centers were facilities established exclusively or primarily for the assembly-line style mass murder of human beings.

Key Facts

  • 1

    Gas vans were used at the first killing center opened at Chelmno in December of 1941.

  • 2

    Three more camps were opened early in 1942 with the goal of eliminating all of the Polish Jews.

  • 3

     More than 1.1 million people died at Auschwitz, including nearly one million Jews. Those who were not sent directly to the gas chambers were assigned to forced labor.

Killing CentersThe Nazis established killing centers for efficient mass murder. Unlike 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." German SS and police murdered nearly 2,700,000 Jews in the killing centers either by asphyxiation with poison gas or by shooting.

First Use in the Euthanasia Program (Operation T4)

Killing centers first made their appearance in Nazi Germany in the execution of 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, 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-occupied annexed and occupied Poland. The first killing center for the mass murder of Jews was Chelmno, which opened in the Warthegau (part of Poland annexed to Germany) in December 1941. Mostly Jews, but also Roma (Gypsies), were gassed in mobile gas vans there. In 1942, in the General Government (a territory in the interior of occupied Poland), the Nazis opened the Belzec, Sobibor, and Treblinka killing centers (known collectively as the Operation Reinhard camps) to systematically murder the Jews of 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 the gas chambers. Chelmno and the Reinhard camps used carbon monoxide produced by diesel exhaust to murder their victims.


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 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 Birkenau killing center using Zyklon B, a poisonous gas. Over a million Jews and tens of thousands of Roma, Poles, and Soviet prisoners of war were killed there by November 1944.


Though many scholars have traditionally counted the Majdanek camp as a sixth killing center, recent research had shed more light on the functions and operations at Lublin/Majdanek. Within the framework of Operation Reinhard, Majdanek primarily served 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: Belzec, Sobibor, and Treblinka II. It also contained 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, special prisoner units (the Sonderkommandos) 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 used 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.

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.

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

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