During the Holocaust, the SS murdered at least 152,000 people at the Chelmno killing center, about 30 miles northwest of Lodz, Poland. It was the first stationary facility where poison gas was used for mass murder of Jews. The killing center consisted of a manorial estate in the town of Chelmno and a nearby large forest clearing. Camp staff and guards were housed in other buildings in town. The estate and the forest camp were encircled by high wooden fences.
The SS and police began killing operations at Chelmno on December 8, 1941. Initially, the victims were Jewish residents of nearby areas transported to Chelmno by truck. SS officials, often wearing white coats like physicians, told the deportees that they would go to Germany as laborers, but first had to bathe. The Jews were led into the house where they were forced to undress and hand over their valuables. Guards directed the naked prisoners down a ramp into the back of a large truck that could hold 50-70 persons. When the truck was full, the doors were closed and sealed. A mechanic attached a tube to the van's exhaust pipe and started the engine, pumping carbon monoxide gas into the truck to kill the prisoners by asphyxiation. After the tube was detached, the van, now full of corpses, was driven to the forest camp, where the bodies were dumped into mass graves. Any prisoners still alive were shot.
On January 16, 1942, the SS and police began to deport Jews in crowded freight trains from the Lodz ghetto to Chelmno. These transports included Jews originally from Germany, Austria, Bohemia and Moravia, and Luxemburg. Other victims murdered at Chelmno included thousands of Roma (Gypsies), as well as several hundred Poles and Soviet prisoners of war. Several dozen Jewish prisoners were forced to remove corpses from the gas vans and bury them in mass graves. Because the graves quickly filled and the smell of decomposing bodies began to permeate nearby villages, in summer 1942 the SS and police ordered that bodies instead be burned on open air “ovens” made of rail track. Periodically, SS and police officials would murder these forced laborers and replace them with new arrivals.
The SS and police conducted killing operations in Chelmno until March 1943 and then again for a brief period in June-July 1944 to facilitate the liquidation of the Lodz ghetto. Beginning in September 1944, a group of Jewish prisoners was forced to exhume and cremate any remaining corpses from the mass graves to obliterate evidence of mass murder. The SS and police shot about half of the 80-man detachment after this work was done. The Germans abandoned the Chelmno killing center on January 17, 1945, as the Soviet army approached.