1942 marked a turning point in the Lodz ghetto, and the Holocaust as a whole, with the full-scale implementation of extermination camps across Europe. In December 1941, the Chelmno extermination centre was established sixty kilometres from Lodz. During January and May 1942 55,000 Jews and 5,000 Sinti-Roma (gypsies) were sent to Chelmno and murdered. The second major deportation occurred in September 1942, often referred to as the Sperre, in which 15,859 children, elderly and ill inhabitants were also sent to Chelmno after the German administration decided to transform Lodz into a total labour ghetto. In order to do so, they required these unproductive elements to be removed.