Out-of-control warders took over the running of the Maze Prison after the IRA escape in 1983, a secret Irish government report states.
Declassified documents show Irish officials warned the British government to take back control of the notorious jail before republican paramilitaries starting killing "easy target" prison officers.
Dublin's then Foreign Affairs Minister Peter Barry was so worried about events inside the Maze, he despatched an underling to the British Embassy to make his concerns known.
In that meeting, the official describes the situation as "potentially explosive".
"It is our understanding that the prison officers and their association are virtually running the prison, independent of the management of the prison which is powerless at present in enforcing its wishes," a note of his remarks states.
"There is a danger of confrontation between the minority and the authorities reminiscent of the hunger strike as the facts begin to emerge.
"It is likely that the paramilitaries on the outside will react violently by killing prison officers and that we would strongly advise the British authorities to exercise command of the prison and ensure that all in the prison (prisoners and wardens alike) accept the norms of prison behaviour and act in accordance with prison discipline and within the prison regulations."
Tensions were at boiling point inside the high-security facility after 38 republican prisoners escaped on September 1983, in what was the biggest mass breakout in British penal history.
In a further memo from the time, marked "Secret", an Irish government official says he was satisfied members of the Prison Officers Association were "acting against the wishes of the prison authorities" and bore responsibility for the tensions.
It adds: "There have been inordinate beatings of prisoners, despite denials by the Northern Ireland Office."
Two sources for the Irish government at the time were Father John Murphy, Catholic chaplain inside the Maze, and Father Denis Faul.
In one report in the Foreign Affairs files, Father Murphy told a government official that the only way inmates could have got weapons for the break out was through collusion from prison officers.
"There are suggestions among the prison officers that money may have changed hands, and one prison officer mentioned to him that certain bank accounts should be checked," it states.
The memo details ill-treatment of inmates in the aftermath of the escape including their being stripped naked, dragged across the compound, leaving lacerations on their backs and buttocks.
Eighteen inmates were said to have suffered dog bites.
"The prison officers, who are almost without exception poorly educated Protestants, have taken complete control," the Irish government files state.
"There is blatant sectarianism within the prison."
In another note marked confidential, it says wardens were completely ignoring instructions from the second-in-command at the Maze, a Catholic, not to beat prisoners.
It also states prison officers demanded in vain to be issued guns by prison management.
The situation was top of the agenda during a meeting between then Secretary of State for Northern Ireland James Prior and Irish Foreign Affairs Minister Mr Barry at Hillsborough on October 19 1983.
Briefing notes for the talks direct the minister to raise evidence showing the ill- treatment by prison officers, "who seem to have taken effective control of the prison".