Latest: Gardaí investigating if Kerry murder may have been over 'noise levels from machinery'

Latest: Superintendent Dan Keane of Listowel Garda station later confirmed the investigation had been upgraded.

Update 6.05pm: Superintendent Dan Keane of Listowel Garda station later confirmed the investigation had been upgraded.

"It was discovered that this was a suspicious death and since then a murder inquiry has been launched," he said.