Two prisoners used a makeshift knife to take another inmate hostage in a cell at Dublin's Mountjoy Prison yesterday.
The incident took place at 3pm, lasted about 30 minutes, and was resolved by prison negotiators and a control and restraint team.
It is believed the disquiet was due to a proposed transfer of prisoners out of Mountjoy.
The Irish Prison Service confirmed that an incident took place yesterday which was resolved peacefully and without injury to staff or prisoners.