THE Mountjoy Separation Unit is a prison within a prison for the most disruptive and dangerous inmates.
The need for a special secure unit for violent prisoners in the early 1980s reflected a turn towards increased violence among criminals. More violence was being perpetrated in society and the disruption was following the tide of offenders into Mountjoy.
Disruptive prisoners had formerly been kept in a small isolation unit known as B Base, but this proved inadequate to meet the increasing demand for space to accommodate the stream of young, violent prisoners who could not fit in with the general prison regime.
The former officers' mess on the fourth floor of the old prison hospital building at Mountjoy, which had fallen derelict, was rebuilt with mass concrete walls and roof, and steel doors. It became the home for inmates who attacked prison officers or other inmates, or who could not fit into the wider prison regime for a variety of other reasons.
Two of the prisoners involved in this weekend's incident have received additional prison sentences for assaults on prison officers - one for three years and the other for two years. A third is reported to have broken a prison officer's fingers in Mountjoy before being moved to the separation unit.
The unit, which can hold up to 20 prisoners, has contained some of the most difficult and dangerous inmates to have gone through this State's penal system, but none quite as dangerous as the current residents, according to sources in the prison.
From the mid 1980s the separation unit increasingly became home for HIV-positive or AIDS prisoners, who were kept in the unit because the prison had no adequate medical unit to look after them. The disruptive prisoners were spread around the prison system as space in the separation unit disappeared.
This situation was accepted as being inadequate, both from the point of view of the men in the unit and the disruptive prisoners who were being spread throughout the system.
Edward Ferncombe, one of the men involved in the latest Mountjoy incident, virtually caused a staff rebellion in Limerick Prison in April 1992 when he attacked a prison officer, breaking his jaw. Ferncombe's attack was followed by allegations that in disturbances which followed, prison officers assaulted another prisoner. The incident was investigated and no charges were brought against officers.
When the new health care unit was opened in Mountjoy in May 1993 the separation unit returned to being used exclusively for disruptive prisoners.
Staffing levels in the unit are around one prison officer to one inmate because of the threat of violence.
The unit's cells are laid out along a single corridor with a recreation room at one end. Access is strictly controlled.
Ironically, the steel doors and other security apparatus which make the separation unit so secure also make it virtually impossible to storm it without giving the prisoners time to harm their hostages.