Dissident republican prisoners are allowed to operate their own regimes within a maximum security prison at Portlaoise in the Republic, it can be revealed.

Members of one renegade terror group, the INLA, now heavily involved in “ordinary” crime, stage daily “military” drills before they are locked up by staff for the night.

Visitors to the republican section are excluded from drug searches by the dog unit as they enter the jail. And the subversives are granted special concessions including the purchase of steak from outside the jail a few times a year to boost their daily food menu.

Details of the regime for the 48 subversive prisoners, currently locked up in Portlaoise, were outlined yesterday at the annual conference of the Irish Prison Officers Association (POA) in Castlebar.

The conference was told that the prisoners also had murals painted on their walls that resembled those found on gable walls in west Belfast.

Both of the Irish main opposition parties condemned the “special treatment” given to republican prisoners. Fine Gael justice spokesman Charlie Flanagan said the reports of prisoners marching and holding parades were “disturbing”.

“It is intolerable that prisoners who have been jailed for subversive activity be allowed to determine their own prison conditions, which is presently the case in Portlaoise,” he said.

And Labour party justice spokesman Pat Rabbitte said there should be no special treatment for prisoners in Portlaoise.

But government sources have dismissed the claims of special treatment as “claptrap”.

They believe they are designed to embarrass prison authorities, who recently moved to eliminate outdated work practices in Portlaoise, which could affect the earnings of prison officers.

A spokesman for Justice Minister Dermot Ahern said the claims by the POA about prisoners marching up and down were “outlandish” during the “white heat of their annual conference”.

The prison is currently experiencing a “dirty” protest, which was launched after Mr Ahern ordered a clamp down on prisoners' temporary and compassionate release, in the wake of the Real IRA murder of two British Army soldiers at Massereene Barracks. It is being staged by six Real IRA prisoners, attached to the faction formerly led by Liam Campbell. It has been on-going for the past 18 days.

The protest POA deputy general secretary Eugene Dennehy said that staff were now working in appaling conditions in the jail. He pointed out that flaps had been placed on CCTV cameras to prevent officers from watching what was happening on the landings.

Four landings of the prison are occupied by subversive prisoners, comprising 10 members of the Real IRA led by former chief of staff Michael McKevitt, 15 members of the opposing faction formerly led by Liam Campbell, 15 members of either the INLA or non-aligned prisoners, and 8 members of the Continuity IRA.