Further revelations of British Army's 'dirty war' as mole in the IRA's killing squad is exposed

Yet another intelligence scandal is surfacing in Northern Ireland, revealing a nightmare world without a moral compass in which agents of the state are accused of complicity in murder.

Less than a month ago, Sir John Stevens, the Metropolitan Police Commissioner, concluded that security forces colluded in at least two murders in Northern Ireland. Now the saga of the agent known as "Stakeknife" is coming to the fore. Although some of the more lurid reports have yet to be substantiated, it looks as though another can of worms has been opened.

Again, an important informer is at the centre of events. Stakeknife was a senior IRA figure for many years who also acted as an agent for British Army intelligence. He was of such value to the Army that he was paid tens of thousands of pounds annually, with the flow of information from him handled by a special military intelligence section. He was clearly one of the Army's most important sources within the IRA.

Inside that organisation, he rose through the ranks to become at one stage a key figure in what was known as the IRA "security department," also known as the "Nutting Squad". (Nutting is IRA jargon for killing.) The irony is that the purpose of this squad was to scrutinise the ranks of the IRA, searching for informers and agents of the security forces.

Stakeknife was an agent involved in tracking down other agents within the IRA. It was brutal and deadly work.

Many people, both IRA members and others, were picked up by the squad and interrogated for lengthy periods of time. Sometimes they were held in Belfast, but on other occasions they were taken to isolated farmhouses in remote border areas where they could be held for weeks.

A flavour of the pressures they faced was given some years ago by Sandy Lynch, a security forces informer who was held in a west Belfast house and questioned by a team from the security department, which is believed to have been led by Stakeknife.

He said he was seized, blindfolded and searched by a gang of men. "I was told I would be taken out and shot for being a touting bastard," he said. "One told me he was from the Northern Command, that he had been trained in Libya and that he enjoyed his work and that he would break me."

One of the chief interrogators said to him: "Do you know who I am, Sandy? You should because we talked before Christmas. You know me but I don't give two fucks, because where you're going you'll not be telling nobody."

Mr Lynch said: "When he was speaking to me he was very aggressive and swore a lot. He said if he had his way I would get a jab in the arse and I would wake up hung upside down in a cow shed. And he would talk to me the way he wanted to talk to me, and he would skin me alive and nobody would hear me squealing." Under this pressure, he confessed but was rescued by the security forces.

Society has always accepted that the security forces should attempt to penetrate groups such as the IRA through the use of informers, who are viewed as a distasteful but essential element of the fight against terrorism.

Their existence poses the question, however, of how deeply they may become involved in illegality. Some law-breaking is inevitable, since joining the IRA is an offence. In the case of Stakeknife, however, the agent appears to have been much more deeply involved, taking part in a series of murders, some of which happened during his time in the security department.

As one of the Army's most valuable agents, his work must have led to security forces' successes and many instances in which lives were saved. But when this is set beside his own involvement in deaths, questions of morals arise.

His work in the security department is a particular example. Over the years, the IRA "executed" more than 50 people, including 16 members of the organisation, seven ex-members and 24 others.

Mr Lynch was rescued from death – perhaps through the intervention of Stakeknife – but others were not so fortunate.

The appalling image is conjured up of Stakeknife, and presumably his Army handlers, knowing that certain people were under interrogation and would probably be killed but taking no action to intervene.

In intelligence terms, the more that is known about the enemy the better. But in these cases, with such a high degree of knowledge, the Army appears to have been playing God in deciding who might live and who might die. Furthermore, some of those killed as informers appear not to have been engaged in passing information to the security forces at all. Stakeknife may well have presided over their deaths.

The world of informers and agents has always been a murky and questionable business but the Stakeknife saga has exposed practices so sordid and, indeed, of such illegality, that no government or security force could possibly stand over them.

The Stevens inquiry still has a long way to run and the detectives involved are at the early stages of looking into the Stakeknife saga. There is much talk that inquiries such as this, and the investigation into Bloody Sunday, last too long and cost too much.

The Bloody Sunday inquiry was set up in 1998 and is not expected to conclude until 2004. It moved to London from Derry in Northern Ireland last year. But the issues raised by the Stakeknife affair are so profound that it is inevitable that there will be calls for more comprehensive, probing investigations into the security forces and the IRA.

It seems that the years ahead hold more revelations.

Agents and whistleblowers

KEVIN FULTON

Kevin Fulton, a double agent who infiltrated the Provisional IRA, claimed to have warned of an imminent bomb attack three days before the Real IRA atrocity at Omagh.

Fulton claimed that he had received information that a well-known dissident republican terrorist was making a large bomb. He claims he passed on the terrorist's name and car registration to his handler at the RUC, who wrote a report to be seen by senior figures within the intelligence community and the Army. He claimed that he was told by a senior member of the Real IRA that "something big" was planned and there were clear signs that his contact was making a bomb.

While he did not specifically mention Omagh, where 29 people were killed in August 1998, the disclosures prompted the Northern Ireland police ombudsman to launch an inquiry that backed up his story, despite the denials of the RUC.

He was told last month that the Government would not help him move from Northern Ireland.

BRIAN NELSON

Brian Nelson was the British agent at the centre of allegations of security force collusion with loyalist paramilitaries in Northern Ireland.

He was a former senior Ulster Defence Association (UDA) member recruited by military intelligence at the height of the Troubles.

Nelson, who was deeply implicated in the murder by the UDA of the Belfast solicitor Pat Finucane in 1989, died last month in Canada, just before the publication of the report by Sir John Stevens, the Metropolitan Police Commissioner. When Sir John was asked to investigate alleged collusion in the early 1990s, he uncovered Nelson's activities and had him charged. Nelson subsequently pleaded guilty to 20 charges, including five of conspiracy to murder, and was jailed for 10 years. Sir John believes many of those involved in running Nelson as an agent should also be charged with offences such as conspiracy to murder.

MARTIN INGRAM

An Army whistleblower known as Martin Ingram exposed evidence of illegal activities by the security forces in Northern Ireland.

In a series of articles printed in The Sunday Times, Ingram revealed the activities of the Force Research Unit (FRU), a covert Army intelligence cell.

He claimed that figures within the intelligence community organised the burning of a police office in Carrickfergus in 1990. The office was being used by detectives under Sir John who were investigating the leaking of intelligence to loyalist paramilitaries. He also said weapons recovered from IRA dumps were returned to protect its agent and used to kill a soldier. Ingram became a key witness for the Stevens inquiry.

Paul Peachey