Gardaí investigating the abduction, beating and torture of businessman Kevin Lunney last September have made another arrest.
The detention of the suspect in his mid-50s follows the arrest last week of four suspects who were released without charge after being questioned.
Another four men are also currently before the courts having been charged with a number of offences relating to the attack on Mr Lunney.
The latest suspect arrested was detained by gardaí on Thursday and was taken to Cavan Garda station for questioning.
He was being held under section 50 of the Criminal Justice Act, which allows for the detention of a suspect for up to seven days without charge.
Mr Lunney (50), a father of six, was abducted close to his home in Co Fermanagh on September 17th as part of the ongoing campaign of violence and threats against executives at Quinn Industrial Holdings.
His leg was broken and the letters QIH were carved into his chest during the 2½-hour ordeal before he was dumped on a roadside in Co Cavan.
A major Garda-PSNI joint inquiry has been under way since the attack, which was a major escalation of the campaign against the executives.
Cyril McGuinness, also known as Dublin Jimmy, was regarded as the leader of the Border gang that has been attacking and intimidating the QIH executive team in recent years.
McGuinness, a Dublin man who had long settled in Co Fermanagh, died of a cardiac event last November when English police raided a safe house he was staying in near Buxton in Derbyshire.
