PRISON authorities have defended the expenditure of nearly €400,000 on a new development at a jail, which they are hoping to close as soon as possible.

The Irish Prison Service confirmed that a significant refurbishment project of the separation unit at Mountjoy jail was currently underway.

The new unit will provide 50 additional spaces with in-cell sanitation at the Victorian prison, which has been chronically overcrowded for years.

The service said the new cells would be used primarily for the protection of vulnerable prisoners who had been threatened and whose lives might be at risk in the general population.

In August 2006, in a high-profile incident in the basement protection area of the jail, inmate Gary Douche was murdered in a cell shared by seven men.

The service justified the expenditure despite plans to shut the jail and move to a greenfield site at Thornton Hall in north Co Dublin. It said it expected the cost of the project to be between €350,000 and €400,000. A statement from the Irish Prison Service said: "The provision of these additional spaces... will provide a more enhanced regime for protection of prisoners than is currently available.

"The Irish Prison Service must maintain Mountjoy as a functioning prison until such time as Thornton Hall is open and improve conditions there where possible – as has been highlighted in reports by the European Committee for the Prevention of Torture and Inhuman or Degrading Treatment or Punishment, the Inspector of Prisons, the Prison Visiting Committee and others."

The service also denied that significant portions of a new €6m complex at Loughan House, Co Cavan, were lying idle due to the recruitment freeze. Two workshops fitted out as part of the project have not been opened because there was no way to hire the required supervisors to staff them.

"The new unit in Loughan House is fully operational and has greatly increased prisoner population at Loughan House," a spokesman said.

He added: "There is no question that large portions of the facility are not being used. There are two workshops, which require an assistant industrial supervisor to become operational.

"However, due to the moratorium on recruitment and promotions in the public service, we have not been able to fill these posts."

The service said it was in the process of a modernisation programme and a plan to provide extra spaces for inmates.