Sachsenhausen concentration camp had operated since 1936 as punishment facility rather than an extermination site. About 30,000 people are believed to had died there from overwork, ill-treatment and malnutrition, although a proportion were put to death by shooting, hanging and, in later years, a gas chamber.

Rumour also had it that the coming night would be still worse. Last night many were awakened by shots in the camp. This was what happened: when a party of those who had been taken from the blocks under cover of darkness marched out of the gate and turned to the right, they realised where they were going, broke the ranks and ran into the little park there between the walls. The guards opened fire on them, and they were shot down there in the park. It was the rat—tat of the guards’ tommy-guns which broke the night silence, filling those who lay awake with horror and dread.