At least 37 people suspected of illegal mining have died while in the custody of Nigeria’s security authorities in the north-central state of Niger, prompting multiple investigations and growing public concern over the conditions in which the detainees were held.

The victims were among dozens of people arrested by the Nigeria Security and Civil Defence Corps (NSCDC) during operations targeting suspected illegal mining in the M.I. Wushishi and Lukoto areas on September 15 and 16, according to Nigerian authorities.

The NSCDC initially attributed the deaths to a suspected disease outbreak, but said the exact cause had not been established. The bodies were transferred to Minna General Hospital for medical examinations and autopsies.

However, accounts from survivors have raised the possibility that overcrowding and inadequate ventilation inside the detention facility contributed to the deaths. One survivor said dozens of detainees had been packed into a poorly ventilated cell and began struggling to breathe.

The father of one survivor, Abdullahi Dalhatu, told the BBC that his son escaped because he was positioned near a small window. He said his son's friend collapsed and that many other detainees also fell unconscious as conditions inside the cell deteriorated.

According to the account, detainees repeatedly banged on the cell door seeking assistance but were unable to get help.

Niger State Governor Mohammed Umaru Bago has described the deaths as “sad” and “tragic” and declared three days of mourning. He said investigators were examining several possible causes, including suffocation caused by overcrowding and possible exposure to hazardous chemicals associated with mining.

The governor also announced the suspension of the NSCDC commandant in Niger State and his team to facilitate the investigation. Separate inquiries have been initiated by the state government, police, the Department of State Services and the NSCDC.

Police have opened their own investigation and are seeking information from relatives and others who may have witnessed the events surrounding the deaths.

The incident has also triggered protests in Minna. Security forces used tear gas during demonstrations on Friday as relatives and other protesters gathered to demand answers over the deaths.

Amnesty International has called for an independent investigation, saying the inquiry should examine not only the cause of death but also the circumstances of the arrests and the conditions under which the suspects were detained. The organization has also raised concerns that some of those arrested may have been minors.

Illegal mining remains a major concern in Niger State, which is rich in gold and other mineral deposits. Nigerian authorities have intensified enforcement against unlicensed mining, which officials and analysts have also linked to environmental damage and, in some areas, criminal networks and armed groups.

The immediate cause of the 37 deaths remains officially undetermined, with forensic examinations and autopsies expected to provide further evidence. (ILKHA)