Alistair Cowan was found hanging in his cell in Newport police station at 11.20am on 11 February. He was transferred to the Royal Gwent hospital in Newport where he was pronounced dead at 9.30am yesterday.
Mr Cowan had earlier attempted suicide when he had been arrested on Friday. The Royal Gwent hospital had treated him and he was taken back to Newport police station.
Even before he had died, Gwent Constabulary voluntarily referred the incident to the PCA for a supervised investigation.