Around 100 prisoners were let out of their cells causing a serious risk to prison staff.
The incident at Maghaberry over the weekend was reportedly caused by an electrical fault.
An officer contacted the Newsletter and claimed the doors on the cells 'unexpectedly opened'.
The Northern Ireland Prison Service confirmed there were two fire incidents on two wings at the high security facility.
Prisoners set fire to rubbish at Bush House on Saturday and Erne House on Sunday.
No inmates or staff were injured and no evacuation was necessary.
Man injured after house and three vehicles set alight in Co Antrim
IT system for Northern Ireland schools ‘largely restored’ following cyber attack
£100 home heating oil grant to be paid out by ‘summer at earliest’
Arrest made after hot water thrown over man at Co Tyrone court
Stormont urged to address ‘catastrophe’ in hospital emergency departments