The main camp as well as the Trawniki and Poniatowa subcamps of the Majdanek extermination camp were surrounded by SS and the Reserve Police Battalion 101 (a unit of the German Order Police from Hamburg) augmented by a squad of Hiwis called "Trawniki men" from Ukraine. The Jews were taken out of the camps in groups and shot layer upon layer inside the pits dug specifically for this purpose. The burial site resembled a "solid mass of women's and men's bodies heaped together... with legs and arms interlinked."[3]