Nigerian police have launched an investigation into the deaths of 37 individuals accused of illegal mining who died while in the custody of the Nigerian Security and Civil Defence Corps (NSCDC) in Niger state. Local officials, including state governor Mohammed Umaru Bago, have described the deaths as "sad and tragic." The NSCDC has suggested the deaths may have been caused by an outbreak of diphtheria, a serious bacterial infection. However, relatives of the deceased have contested this explanation, claiming the detainees were deliberately killed. An intelligence report shared with AFP news agency indicated that overcrowding and poor ventilation within the detention facility may have contributed to the fatalities. In response to the incident, an NSCDC commander has been detained, and the state's police chief has ordered an immediate investigation. The bodies of the deceased have been sent to a general hospital in Minna for examination. The region of Niger state is known for small-scale gold mining, and officials and experts have linked the scramble for gold reserves from illegal mines to fueling criminal gang violence.