Four prison officers have been injured after an incident at Maghaberry Prison in Co Antrim yesterday.
Northern Ireland's Department of Justice confirmed that the four officers were injured after an incident with a prisoner.
One female officer needed treatment for her injuries.
The Prison Service in the North will carry out a full investigation into the incident.
It comes after a report into the high security prison last year labelled Maghaberry the most dangeous prison ever inspected by UK authorities.