A man, who was arrested on suspicion of the murder of an inmate at Cloverhill Prison in Dublin, has been released without charge.
Martin Salinger, from Ballyfermot in Dublin was found dead in an overcrowded cell in the early hours of Saturday morning, Irish broadcaster RTÉ said.
A man, in his 30s, was arrested on suspicion of murder.
He released and returned to custody at the prison on Monday.
A second inmate received treatment for injuries which have been described as non-life threatening, RTÉ has said.
Gardaí (Irish police) have said that a file will be sent to the Director of Public Prosecutions.
Irish Minister for Justice Helen McEntee has said there will be 150 more prison spaces and the budget will go up by 70% in 2025.
An investigation into the death in custody of Salinger will also be carried out.
