The head of the Prison Officers' Association has claimed that his members are facing new loyalist death threats.
Mr Finlay Spratt said: "UDA has said prison officers' homes will be attacked," and his remarks follow the discovery of suspicious devices under the car of a prison officer's daughter, and at a pub in Maghaberry, Co Antrim, near the prison.
Both were later declared elaborate hoaxes.
The intimidation threat follows the separation of loyalist and dissident republican prisoners at the jail after a summer of disturbances by inmates and a no-wash campaign. There has been a spate of attacks on the homes of prison officers.
The British government announced the move to separate prisoners last month following publication of the Steele report into the Maghaberry regime. However, the government resolutely insists there is no return to the Maze-style segregation which permitted paramilitaries to run their own wings of the prison.
Mr Spratt said: "We have always said it doesn't matter what measures were brought in, the attacks will not stop because these people's agenda won't stop. They will not be satisfied until they achieve segregation on a level of the old Maze prison.They are not worth recognition within society, any of these groups making threats."
Prison sources said police told the authorities they had information to suggest officers were under threat. It is believed, however, that similar intelligence is regularly passed on.