More than 20 prisoners at Wheatfield Prison in Dublin are to face disciplinary action following an incident involving the crash landing of a remote-control helicopter carrying drugs into the facility.
It is understood the prisoners were awaiting the drugs in a yard.
An inmate was intercepted after he was seen hiding a quantity of the substance on his person and he is now being held at a secure location on-site until he produces the drugs.
The device has been handed over to officers at Ronanstown Garda station in Clondalkin and the incident will be investigated by Gardaí and the Irish Prison Service.