Three Gardaí were suspended from duty as part of the investigation in May.
A man in his early 50s was arrested on Thursday (4 July) for suspected conspiracy to pervert the course of justice and detained at a Garda Station in Tipperary under section 4 of the Criminal Justice Act 1984.
He was subsequently released without charge and the investigations are ongoing.
The arrest is in relation to investigations by personnel attached to the Garda National Bureau of Criminal Investigation (GNBCI) into alleged wrong-doing or corruption involving Garda personnel in the Southern Region.
In May, two Gardaí, a superintendent and a ranked Garda, were arrested in an investigation into alleged links between members of the force and a criminal gang.
A Garda inspector was also detained as part of the investigation; all three were released without charge at the time and suspended from duty.
LISTEN: You Must Be Jokin’ with Aideen McQueen – Faith healers, Coolock craic and Gigging as Gaeilge
