Protests have erupted in Minna, Niger State, after dozens of suspected illegal miners died while being held by the Nigeria Security and Civil Defence Corps, prompting investigations into one of the most serious recent incidents involving deaths in the custody of a Nigerian security agency.

Reuters reported on Friday that at least 33 detainees died after being arrested during operations against suspected illegal gold mining in the Wushishi and Lukoto areas on September 15 and 16.

Niger State Governor Mohammed Umaru Bago has separately said 37 people died in custody, meaning the final confirmed death toll remains subject to official reconciliation.

The deaths triggered protests in Minna on Thursday night, with angry residents taking to the streets demanding answers over what happened to the detainees.

PROTESTS ERUPT AFTER DEATHS

Residents protested overnight after news of the deaths spread across the Niger State capital.

Some protesters blocked roads while vehicles were damaged during the unrest, according to Reuters.

Security personnel were deployed across parts of Minna by Friday morning as authorities moved to restore calm and prevent further disturbances.

The unusually high number of people who died while in state custody has intensified demands for authorities to establish exactly what happened between the arrests and the discovery of the bodies.

MINERS ARRESTED DURING SECURITY OPERATIONS

The detainees were among scores of people arrested by the NSCDC during operations targeting suspected illegal mining on September 15 and 16.

The raids took place around the Wushishi and Lukoto areas as part of efforts by security authorities to combat illegal gold mining in Niger State.

The NSCDC said various exhibits were recovered during the operations.

The detainees were subsequently held at an NSCDC facility in Minna.

CAUSE OF DEATH REMAINS UNDETERMINED

The Niger State NSCDC initially said the detainees were found dead following a suspected outbreak of disease.

However, the agency's national headquarters later stressed that the actual cause of death had not been established and would require medical and laboratory examinations.

The bodies were taken to the General Hospital in Minna for examination.

Separate accounts from survivors have raised allegations about overcrowding and poor ventilation inside the detention facility. Those claims have not been established as the cause of the deaths and are expected to form part of the investigation.

NSCDC COMMANDANT SUSPENDED

Nigeria's Interior Minister Olubunmi Tunji Ojo has suspended the Niger State NSCDC Commandant, Suberu Siyaka Aniviye, pending a full investigation into the incident.

The NSCDC has also established a high powered investigative team led by its Deputy Commandant General responsible for Intelligence and Investigation.

Investigators are expected to examine the condition of the detainees when they were arrested, the conditions under which they were held, the length of their detention, medical attention provided and the circumstances surrounding their deaths.

Niger State Police have opened a separate investigation.

GOVERNOR DECLARES THREE DAYS OF MOURNING

Governor Bago described the deaths as tragic and announced three days of mourning for the victims.

He also said a committee of inquiry had been established to investigate the circumstances surrounding the incident.

The investigation will be closely watched because of the scale of the deaths and questions surrounding the treatment and protection of people held by security agencies.

Authorities have urged residents and relatives of the deceased to remain calm while medical examinations and investigations continue.

The central question remains what caused so many detainees to die within such a short period after being taken into custody.

Until medical findings and the investigations are completed, authorities have cautioned against drawing conclusions about the cause of death.