Chełmno, located about 50 miles northwest of Łódź, was the first operational death camp. The camp opened in late 1941 with the purpose of murdering Jews and Roma in the Łódź ghetto and the Wartheland district.
Killing operations under the supervision of the SS began on December 8, 1941. The first victims were Jews from the Wartheland district who were brought there by truck. Later, Jews were brought to the camp by train from the Łódź ghetto. They were murdered in vans by carbon monoxide and their bodies burned. Some 147,000 Jews and 5,000 Roma were killed at Chełmno from 1941 to 1944.
The Germans abandoned the camp in early January 1945 as the Soviet Army approached. The Chełmno death camp was liberated on January 17, 1945.
The following summary derived information from the Encyclopedia of the Holocaust.