The praise came at the Special Criminal Court where two of the men arrested were each given 6 and a half years sentences for IRA membership.

Mr Justice Paul Butler, said "a very successful garda operation" was launched after an off duty garda spotted ten men in two cars acting suspiciously on the M1 and followed them.

The judge said that eventually Garda Brian Daly and Garda Enda Muldoon, of Santry Garda Station, stopped the cars in Balbriggan and found the men inside dressed in paramilitary type gear.

Mr Justice Butler said the two gardai were “quite heroic” and deserved much praise” for that.

Derek Palmer , a father of seven, of Corduff Green, in Blanchardstown, and Joe Clarke a father of four, of Geraldstown Woods, Santry, were convicted at the non-jury court last month of IRA membership on July 14th, 2011.

Both men had denied the charge.