Gardaí are investigating the death of an inmate at Cloverhill Prison in Dublin yesterday.
The man, who was in his 30s, died after he was being taken back to his cell by prison officers.
He was on remand for a breach of a barring order and was due to appear by video link before Cloverhill court.
However, it appears a situation developed and prison officers intervened to control and restrain the inmate.
A post-mortem is being carried out to determine the cause of the man's death.
Gardaí along with the Prison Service and the Inspector of Prisons are now examining all the circumstances surrounding the incident.
The Prison Service would not comment on the incident.