Irish police have arrested two males and a girl over the kidnapping and torture of Quinn Industrial Holdings (QIH) director Kevin Lunney.
The three individuals are being held in custody after searches had been carried out in counties Cavan, Longford and Dublin, Irish broadcaster RTÉ has reported.
Mr Lunney was kidnapped and attacked on 17 September.
He was dumped on a highway in County Cavan, Republic of Ireland, 22 miles (35km) from the place he was kidnapped.
Mr Lunney, a father of six, had his leg damaged, was slashed with a knife and doused with bleach in a two-and-a-half hour ordeal.
The 50-year-old had the letters QIH reduce into his chest with a knife and instructed the BBC’s Spotlight final week that he feared that he would by no means see his spouse and youngsters once more.
A suspect within the investigation into Mr Lunney’s assault died on final Friday throughout a police raid in England.
Cyril McGuinness, 54, is thought to have suffered a coronary heart assault as police searched his Derbyshire dwelling.
That search was a part of a joint police operation throughout the UK and Ireland through which nearly 20 properties had been raided.
The PSNI mentioned it could “continue to work closely” with the Garda Síochána (Irish police) and Derbyshire Constabulary to attempt to “bring the perpetrators to justice”.