Eight prisoners who staged a rooftop protest at a jail in Co Antrim are back behind bars tonight.
Prison authorities managed to get the inmates down from the roof at Maghaberry Prison near Lisburn after a day of intense negotiations.
Northern Ireland Prison Service director general Mr Peter Russell has now ordered a major security review in a bid to ensure that there no repeat of the incident, which involved loyalists, republicans and non-terrorists.
"Clearly we will have to look at how the prisoners gained access to the roof and other aspects of the incident to see what lessons we can learn," Mr Russell said.
The inmates at Maghaberry, which houses some of Northern Ireland's most notorious criminals and terrorists, began their protest last night over alleged overcrowding.
But only half of those involved in the stand-off on top of Roe House wing actually shared cells, the prison service said.
All visits to the jail were suspended today as jail managers studied the protesters' demands.
Once they were safely back in their cells, a prison service spokesman insisted: "No concessions were made."
A hoax bomb alert added to the security headache, with 15 other inmates in the exercise yard cut off from the main building while British army explosives experts dealt with the fake device.
Mr Finlay Spratt, of the Prison Officers Association, had claimed that management was warned two weeks ago trouble was brewing over staff cuts and the large prison intake.
Among those held at the high-security complex are feared loyalist terror boss Johnny "Mad Dog" Adair - and some of his most powerful enemies within the feuding Ulster Defence Association.
Mr Spratt said: "We as prison officers who have quite an experience of dealing with prisoners in the Northern Ireland Prison Service have been continually saying to management that their policy of doubling these prisoners up was actually going to lead to what is happening."
Dissident republican terrorists kept in Maghaberry have previously warned their lives were under threat because they were held close to loyalists.
But after both sides joined the protest, a security source dismissed their claims, saying: "They say it's too dangerous being housed with loyalists, yet they got up on a roof with them.
"I can't think of a less safe place to be with your supposed sworn enemy."
PA