SENIOR garda anti-terrorist officers are seriously concerned about links between the socialist republican group, Eirigi, and an armed raid on a gun shop.
A number of Eirigi sympathisers are being questioned by gardai about the incident in which officers from the Emergency Response Unit intercepted an armed gang as they were about to go into the premises.
Two handguns were seized as well as a stolen car, a can of petrol, balaclavas, wigs and gloves. Three men and a woman, all from Dublin, were arrested outside The Tackle Shop, at Rahan, near Tullamore, Co Offaly, on Tuesday night.
A fifth suspect, who is a leading member of eirigi, was later detained at his home in west Dublin. All five are being questioned at Tullamore and Mullingar garda stations under section 30 of the Offences Against the State Act.
Gardai believe eirigi could now have a military wing.
One of those being questioned has a conviction from the Special Criminal Court for membership of an illegal organisation, the Provisional IRA.
Garda evidence was given to the court that the man was part of a Provisional IRA active service unit, attached to the organisation's Dublin brigade.
Another suspect has a conviction for assault, while a third is closely connected to a woman convicted of serious terrorist offences in Northern Ireland.
Eirigi was formed in the summer of 2006 as a republican socialist campaign group and its ranks included a number of disaffected Sinn Fein activists.
At the time, gardai said they were satisfied that Eirigi did not have a military wing but pointed out that they were keeping a close watch on who was defecting to it from the mainstream organisation.
Members of eirigi have been active in demonstrations including the Shell to Sea campaign in Co Mayo, and protests outside the former headquarters of Anglo Irish Bank at St Stephen's Green. It also infiltrated a students' demonstration near Leinster House.
Last year they were prominent in a series of protests over the visit of Queen Elizabeth, alongside members of the 32 County Sovereignty Movement and Republican Sinn Fein.
Gardai said they believed the arrests at Rahan prevented an armed robbery which would have resulted in the theft of a large haul of weapons.
The weapons would likely have been used in robberies around the country.