On registration in the Gypsy Camp, the Norwegian Roma had their prisoner numbers tattooed on their arms with the letter ‘Z’ for Zigeuner (Gypsy) and had a black triangle sewn on their clothes designating them as ‘asocial’ prisoners. This practice placed the Roma in two of the groups classified by the Nazis as enemies: not only were they racially inferior, they were also defined as asocial, mentally retarded and incapable of living a modern way of life. Unlike the other prisoners in the camp, few Roma families were separated on arrival, since the Gypsy Camp was a so-called family camp. They were mostly neither provided with prison uniforms nor deprived of their clothes and possessions, nor were they subjected to a selection process to be sent directly to the gas chambers. One important exception to this rule occurred on the night of 2 August 1944, when around 2,900 prisoners were gassed to death as the camp was being closed.
As in the rest of Auschwitz II, the living conditions in the Gypsy Camp were close to unbearable. The mortality rate was extremely high; even higher than in the rest of Auschwitz. Most deaths were caused by abominable sanitary conditions, extreme malnutrition and epidemics, and excessively high numbers of prisoners. One feature of the Gypsy Camp that contributed to the high mortality rate among the registered prisoners was the relatively high proportion of children, who, naturally, were poorly equipped to survive such extreme conditions. One of the youngest children to be registered on 17 January 1944 was André Modis. He was born on 31 January 1943 and, according to the prison records, died in 1944, presumably shortly after arrival.
The prisoners in the Gypsy Camp were frequently subjected to medical experiments and tests in the camp's medical barracks and the so-called Waffen SS Hygiene Institute. Many of these medical assaults were performed by SS doctors in barrack no. 32, where everything from the taking of blood and urine samples in connection with experiments on typhus and other epidemic diseases to the murder of prisoners to obtain organs for experiments and quasi-scientific research were conducted. More than one-third of the deported Norwegian Roma was subjected to a range of medical assaults, and records on 17 of them were found in the archives of the Waffen SS Hygiene Institute in Auschwitz.
One of them was 15-year-old Milos Karoli. On 15 June 1944, the Waffen SS Hygiene Institute requested a urine sample from a male prisoner in the Gypsy Camp. Milos was selected, and the urine sample was taken the following day, on 16 June. The entire procedure was recorded and signed by SS- Hauptsturmführer Dr Josef Mengele.