Authorities in north-central Nigeria are investigating the deaths of 37 people who were being held in connection with illegal mining, France 24 reports. The detainees died at a detention facility in Niger state, according to officials cited by the broadcaster.

The Nigerian Security and Civil Defence Corps has pointed to a possible disease outbreak as an explanation for the deaths. The report does not identify the illness involved or say when the deaths occurred.

Other reports have suggested that overcrowding and poor ventilation may have contributed to the fatalities. Those accounts raise questions about conditions at the facility, but the supplied material does not provide further details about its capacity, sanitation or medical services.

Authorities are investigating the circumstances surrounding the deaths. The available report does not state whether the investigation has produced findings, whether any officials face disciplinary action or what steps, if any, have been taken at the detention centre.

The detainees were being held over allegations connected with illegal mining. The report does not provide information about their identities, the status of their cases or whether the deaths affected other people at the facility. France 24 correspondent Sam Olukoya reported the details.