the Kulmhof extermination camp began gassing operations on 8 December 1941. Two weeks later, on 20 December 1941, Rumkowski was ordered by the Germans to announce that 20,000 Jews from the ghetto would be deported to undisclosed camps, based on selection by the Judenrat. An Evacuation Committee was set up to help select the initial group of deportees from among those who were labelled 'criminals': people who refused to or who could not work, and people who took advantage of the refugees arriving in the ghetto in order to satisfy their own basic needs. By the end of January 1942 some 10,000 Jews were deported to Chełmno (known as Kulmhof in German). The Chełmno extermination camp set up by SS-Sturmbannführer Herbert Lange, served as a pilot project for the secretive Operation Reinhard, the deadliest phase of the "Final Solution". In Chełmno, the inmates were murdered with the exhaust fumes of moving gas vans. The stationary gas chambers had yet to be built at Operation Reinhard death camps. By 2 April 1942, an additional 34,000 victims were sent there from the ghetto, with 11,000 more by 15 May 1942, and over 15,000 more by mid September, for an estimated total of 55,000 people. The Germans planned that children, the elderly, and anyone deemed "not fit for work" would follow them. In September 1942, Rumkowski and the Jews of Łódź had realized the fate of the evacuees, because all baggage, clothing, and identification papers of their fellow inmates, were being returned to the ghetto for "processing". The slave workers began to strongly suspect that deportation meant death; even though they had never deduced that the annihilation of Jews was all-encompassing, as was intended. They witnessed the German raid on a children's hospital where all patients were rounded up and put into trucks never to return (some thrown from windows). A new German order demanded that 24,000 Jews be handed over for deportation. A debate raged in the ghetto over who should be given up. Rumkowski sounded more convinced than ever that the only chance for Jewish survival lay in the ability to work productively for the Reich without interference. As Rumkowski believed productivity was necessary for survival, he thought they should give their 13,000 children and their 11,000 elderly. He addressed the parents of Łódź as follows. Despite their horror, parents had little choice but to turn over their children for deportation.