A man (53) has been arrested in Co Monaghan as part of an investigation into dissident republican activity.
He was detained following a search of a house and its surroundings in the Carrickmacross area.
The operation involved local gardaí and officers from the Special Detective Unit.
The man is being detained at Carrickmacross Garda station under the provisions of Section 30 of the Offences Against the State Act, 1939.