The Garda Ombudsman is examining the circumstances surrounding the death of a man in his 70s while in custody at Westport Garda Station in Co Mayo today.
The incident was referred to GSOC by Gardaí at about 12.30pm today.
In a statement, GSOC said the man - who was under arrest - became unwell with breathing difficulties and CPR was administered by gardaí.
A doctor and the emergency services were called and the man was pronounced dead at the scene.
The State Pathologist has been informed and a post mortem examination will take place in the coming days.
GSOC investigators are currently at the scene.
The Garda Ombudsman said an independent examination is underway to establish the facts of the situation.
*This story was updated at 5pm in light of new information.