An investigation is underway into an incident at Portlaoise Prison in which inmates threw the contents of their chamber pots at the governor and prison officers.
The incident followed a search of a cell on one of the wings housing republican prisoners.
Reports this morning say prison officers were investigating allegations that an INLA member had created a home-made weapon out of a soup ladle.
A number of inmates subsequently protested that they were being unfairly targeted.
During these protests, two of the prisoners were brought to the segregation unit.
Governor Ned Whelan was later attacked while making his regular rounds of the jail and extra staff were called in to deal with the situation.
The five prisoners involved in the incident are believed to have been punished by being locked in their cells without access to phone calls or visits for a month.