A warder was knocked unconscious when prisoners clashed with staff at a jail in Northern Ireland.
Two other officers were injured when they were attacked at Maghaberry, near Lisburn, Co Antrim.
The trouble flared last night after three prisoners refused to return to their cells after they had been using pay phones.
The officer who was knocked hit his head on a pillar. One officer received cuts behind his ear.
A spokesman for the Northern Ireland Prison Service said today that the jail’s governor Pat Maguire had launched an internal investigation into the incident.
Meanwhile the search for a new director general of the prison service has started. Applications for the job to replace Colin McConnell close on May 4th.
Mr McConnell is moving at the end of next month to head the Scottish Prison Service. The current deputy director director Max Murray will act up until the position is filled.
PA