[intarga]

"Concentration camp" as a term pre-dates the Nazis, and has a specific meaning, which does apply here.

>A camp where persons are confined, usually without hearings and typically under harsh conditions, often as a result of their membership in a group the government has identified as suspect.

I would also note that the term does not apply to places where people in Nazi Germany were gassed or cremated, those have a separate term: death camps.