16 prison officers at Maghaberry Prison near Lisburn in Co Antrim have been suspended from duty.
The suspensions were ordered by Northern Ireland's Prison Service amid an ongoing investigation into the death of an inmate in his cell.
Last August in the early hours of the morning, 34-year-old Colin Bell was found dead in his cell at the jail. It is understood he hanged himself.
Bell had been jailed for life for the murder of a man who died in a fire he had started at a house in Bangor in Co Down.
Soon after Bell's death, a prison officer at Maghaberry was suspended and charged with gross misconduct.
An internal investigation was also ordered and arising from its preliminary findings, a further 16 night custody officers have now been suspended, and the prison service says they will all face charges.
Prison Officers Association Chairman Finlay Spratt said he had no idea yet what charges his members would face.
