The Treblinka extermination camp was run by the SS, a Nazi paramilitary organization, with the help of Eastern European Trawnikis (Hiwis), who were collaborationist auxiliary police recruited directly from Soviet POW camps. The Trawnikis served at all the major extermination camps, including Treblinka. Treblinka was part of Operation Reinhard, the systematic extermination of the three million Jews living in the General Government of German-occupied Poland. It is believed that between somewhere between 800,000 and 1,200,000 people died in its gas chambers, almost all of whom were Jews. More people died at Treblinka than at any other Nazi extermination camp besides Auschwitz.