One of the men arrested by gardai after the discovery of firearms and mortars in Co Kildare at the weekend served in the Defence Forces until three years ago, it has emerged.
The man, in his late 20s, is the fourth member of the Defence Forces to be arrested over alleged offences believed to involve the "Real IRA". He and another man arrested on Saturday morning in Co Kildare were still being questioned by gardai last night.
Both are expected to appear before the Special Criminal Court this morning.
Forensic examination of the weapons recovered at the weekend showed that the two assault rifles and handgun were in good condition. However, the 20 mortars were in poor condition and contained no explosive. It is believed the mortars were manufactured by the Provisional IRA at least a decade ago.
Three ex-members of the regular Defence Forces and one member of the reserve force, the FCA, have now been arrested and questioned about serious offences related to the "Real IRA".
One ex-soldier, John McNamara (39), from Co Kildare, was sentenced to three years in March for the possession of a 980lb bomb in a car he was driving on to the ferry at Dun Laoghaire in April 1998. Gardai believe the bomb was on its way to the Grand National steeplechase at Aintree and was to be detonated at the time of the signing of the Belfast Agreement.
The former FCA member, Thomas Ryan (25) from Co Wexford, was given a suspended sentence last month for stealing 87 sticks of gelignite from the Arcon mine in Co Kilkenny where he worked. The explosives were handed over to the "Real IRA" or its associate group, the Continuity IRA.
Meanwhile, three men from the Cooley peninsula are still in custody in Slovakia awaiting the hearing of an extradition application from British authorities on warrants alleging their involvement in arms-smuggling.
All three suspects are known to gardai. One served a prison term in France in the late 1980s after he was arrested with explosives intended for the Provisional IRA. None of the men has ever faced serious charges in the Republic.
One of the men is a haulier. The other two are described as helpers who own smallholdings in the Cooley area.