The Minsitry of Social Security (MSS) maintains most law enforcement activities. It is one of the most powerful state institutions in North Korea and oversees the national police force, investigates criminal cases and manages non-political correctional facilities. It handles other aspects of domestic security like civil registration, traffic control, fire departments and railroad security. The State Security Department was separated from the MPS in 1973 to conduct domestic and foreign intelligence, counterintelligence and manage the political prison system. Political camps can be short-term reeducation zones or "kwalliso" (total control zones) for lifetime detention. Camp 15 in Yodok and Camp 18 in Bukchang have been described in detailed testimonies.