A man died suddenly in the luxury Ballyfin Demesne hotel in north County Laois last night.
Gardaí were called out just before 8PM and a man, who is in his 30s, was arrested and taken to a Garda Station in the east of the country for questioning.
Meanwhile, a Senior Investigating Officer has been appointed at Portlaoise Garda Station to lead the investigation into the death.
The Garda Technical Bureau and Office of the State Pathologist have all been informed.
The family of the deceased man, who was in his 60s, will be appointed a Family Liaison Officer to support them.
Main image shows Ballyfin Demesne hotel. Image by: Newstalk.