Five prison officers were briefly held captive by prisoners at La Picota jail in Colombia today where Mr Niall Connolly, Mr Martin McCauley and Mr Jim Monaghan are being held.
The three men were arrested last August, on suspicion of training left-wing FARC guerrillas.
"I heard from talking to Niall Connolly in Patio A that some prisoners took guards prisoner," said Ms Catriona Ruane of the Bring Them Home Campaign. "There was a negotiated settlement, but it was reneged on," she added.
Ms Ruane said the prisoners' protest was about conditions and the types of visits. "Other wings in the prison get better visits than the wing where the three Irishmen are being held, she said.
The situation is now under control, but Ms Ruane doubts the calm will continue. The security services baton charged prisoners and used tear gas to quell the unrest.
"They hand-cuffed five or six prisoners," said Ms Ruane "They are to transfer the men to a prison called Valle Dupar 16 hours away by road."
She feels prison stability needs overall agreement amongst prisoners, but believes there are too many factions for this to happen.