Gardaí are to send a file to the Director of Public Prosecutions following the release without charge of four men arrested for questioning about the activities of dissident republicans in Munster.
The four men, all in their 20s, had been arrested in a series of early morning raids on Thursday in Cork city and east Co Cork.
Three were arrested under Section 30 of the Offences Against the State Act, and the fourth under Section 4 of the Criminal Justice Act. The men, who were questioned about firearms offences, were held for up to 16 hours, with the last released at midnight.
The arrests are the latest in a series of operations against the "Real IRA" and follow the arrest and questioning of five men in Cork city and two in Limerick last December about dissident republican activity.
Earlier this week, detectives from Mitchelstown and Fermoy recovered four weapons when they located a small arms dump near Kilworth in north Co Cork, but it is understood that the Cork city and east Cork arrests are not linked to the discovery of that cache.
However, it is known that the "Real IRA" has been active in the Cork city area, and gardaí suspect that the shooting of a man in a chip shop in Blackpool in August 2002 was linked to a protection racket being run by the paramilitary grouping.
Detectives believe that two middle-aged brothers from Cork's south side have recruited up to 20 members for the "Real IRA" in Cork city and surrounding areas in the past two to three years. Two men in their 20s living on Cork's north side have taken over the day-to-day running of the group and have targeted publicans, club-owners and drug-dealers in a series of extortion and protection rackets.