A fire has been extinguished at the Maghaberry Prison in Co Antrim.
The fire started at around 8pm at Bann House, a block containing loyalist and other inmates. It followed disturbances among the prisoners.
There were also reports of a suspect device in the area.
A number of fire tenders were at the scene and it is understood up to fifteen prison officers were treated for shock and smoke inhalation.
Talks to continue on safety in jails
The fire occurred as talks in London broke up for the night between members of the Prison Officers' Association and the Northern Ireland Office about safety in the North's jails.
Industrial action, which could be supported by colleagues throughout the UK, has been threatened over demands for improved security at the homes of prison officers in the North.
The dispute arose following the Stormont police raids in 2002 against an alleged republican spy ring.
Police warned afterwards that the personal details of more than 1,400 prison officers were in the hands of the IRA.
Some officers on the list were helped to move house, but around 600 opted for tighter home security paid for by the authorities under the Key Personnel Protection Scheme.
Now the North's POA says the scheme was inadequate.
However, a spokesman for the Northern Ireland Prison Service said the authorities had committed £28m to improving security or helping prison officers affected move house.
