German authorities have justified their failure to inform the public about the scale of the problem by citing the privacy rights of the criminal offenders.

Experts have long warned that the practice of housing migrants from different ethnic and religious backgrounds in tight accommodations is the ideal breeding ground for violence.

"A maintenance man who worked in a refugee shelter reported 'mafia-like' conditions. Refugees were required to pay for access to the electrical sockets there." — Der Tagesspiegel.

https://www.gatestoneinstitute.org/11264/germany-refugee-shelters