The attack was ordered by the south Armagh OC (officer commanding) and approved by an Army Council member from the area, they claimed. Known in the media as "The Surgeon", the prominent IRA man in his mid40s has been responsible for many killings, although he has never been convicted.

These claims contradict security sources who insist the killing was carried out either by criminals, ex-IRA members or individual low-level Provisionals acting without authority.

While "The Surgeon" gave the go ahead for the beating, it wasn't sanctioned by other Army Council members, sources said.

Gerry Adams and Martin McGuinness are reportedly furious at the political embarrassment the killing has caused.

Paul Quinn from Cullyhanna was lured to a farm near Oram, Co Monaghan. Up to eight men beat him to death with iron bars.

Friends also claimed they used nail-studded cudgels.

Sinn Fein described the murder as a fallout between "criminals" and "fuel-launderers".

However, this is rejected by local people. The Sunday Tribune was given detailed accounts of two rows Quinn had with local IRA members and their associates.

Former Sinn Fein councillor Jim McAllister said Quinn's parked car was rammed by another vehicle three months ago. Quinn caught one of those involved and hit him. The man's father is the south Armagh OC.

The OC is involved in diesel laundering in the area. It is claimed the security forces turn a blind eye to his activities. He also set up a fuel laundering business in England.

Last month, Quinn had a fight with a Cullyhanna man who is a close associate of senior Provisional figures. It is understood the Quinn family will give details of the altercations and threats made by the IRA against their son to gardai investigating his murder.