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 killed with the exhaust fumes of moving gas vans. The stationary gas chambers had yet to be built at death camps of Einsatz Reinhardt.[5] By 2 April 1942 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 the total of an estimated 55,000 people. The Germans planned that children, the elderly, and anyone deemed "not fit for work" would follow them.