THE Scottish army officer who headed up a notorious military intelligence unit is to be questioned under caution by police investigating collusion, murder, kidnap and torture in Northern Ireland during The Troubles.

Brigadier Gordon Kerr, from Aberdeen, ran the Force Research Unit (FRU) which recruited agents within terrorist organisations in Northern Ireland, including the IRA and loyalist paramilitary groups.

The most infamous double-agent working for the FRU was Stakeknife, the British army’s highest placed mole inside the IRA. The Herald newspapers named Freddie Scappaticci as Stakeknife in 2003.

Stakeknife has been linked to multiple murders in Northern Ireland while working as an agent for the British. There have been long-running allegations that British security forces colluded with terrorists, who they were running as agents, in the deaths of civilians.

In January last year Scappaticci was arrested by detectives from Operation Kenova, which is investigating the role of Stakeknife. He was detained in connection with a series of crimes including murder, kidnap and torture, and later released on bail.

Scappaticci has consistently and vehemently denied that he is Stakeknife.

The Stakeknife affair lies at the heart of the ‘Dirty War’ in Northern Ireland. Stakeknife was a top level IRA volunteer who ran the IRA’s Internal Security Unit, the so-called ‘Nutting Squad’ which executed traitors and informers with a bullet to the head after torturing them.

There are claims that Stakeknife and other agents for the British military were allowed by their army handlers to continue operating as terrorists - including carrying out acts of murder - in order to maintain their cover. There are also claims they were used to carry out assassinations.

High level security sources have now confirmed that Kerr will be questioned by detectives from the Kenova team under caution.

Last night, former MI5 agent Willie Carlin, who infiltrated the Irish republican movement in Northern Ireland during the Troubles, and also knew Kerr, said the Scottish officer should be questioned as quickly as possible in order for the truth to be established about the Dirty War, and for the families of victims to achieve justice.

Carlin said it was ‘essential’ that Kerr was formally interviewed by police. ‘Kerr is the man who commanded soldiers who were the handlers for Stakeknife and the Kenova team are investigating the activities of Stakeknife,’ Carlin said.

Carlin said that only by questioning Kerr could the authorities establish who else knew about the role of the FRU. It has been claimed that the activities of the FRU were known about at a senior political level, including the Northern Ireland secretary, Defence Secretary and Prime Minister.

Carlin said that Stakeknife’s FRU handlers were told by the agent about IRA operations which led to deaths but did not act on the information in order to protect their asset.

‘Where does the buck stop?’ Carlin said. ‘Kerr would have had briefings from Stakeknife’s handler and he would have had to pass his reports upwards.’

Carlin, who has spoken with detectives from Operation Kenova, says his home was recently broken into and paperwork relating to Stakeknife, the FRU and Kerr was stolen, along with documents relating to Bloody Sunday. No other material was taken.

During an earlier investigation into collusion in Northern Ireland, by former head of the Metropolitan Police Sir John Stevens, a fire at the offices of investigating officers was blamed on the FRU. A so-called CME (covert methods of entry) team was suspected of being used to obstruct the inquiry.

Carlin said: ‘The FRU was the spearhead when it came to running agents in Northern Ireland. You had IRA, and in some cases UVF, volunteers coming to their handlers and telling them what was happening, who was going to be shot, and it all went into a big melting pot. People sat around tables and decided who was going to live or die in order to protect the informants who brought the information in the first place.’

Agents were also allowed to carry out acts of terror with the knowledge of their handlers in order to keep their cover, Carlin said. ‘By the end of the Troubles, the FRU had agents in practically every IRA unit in the north.’

The extent of the British military’s control over the IRA, through infiltration, is seen by many in both the republican movement, the loyalist movement and the British security forces as one of the key reasons why the IRA eventually chose to pursue peace.

‘The IRA was leaking info all over the place,’ Carlin said. ‘The big question has always been - how do we get the IRA to move from war to a ceasefire. That was the main game that MI5 and the FRU were playing.’

Carlin believes British military intelligence did collude with terrorist organisations resulting in the loss of lives. ‘British military intelligence is supposed to gather intelligence which leads to the arrest and conviction of terrorists. The FRU was doing the opposite. They were keeping terrorists at work, keeping terrorists out there.

‘That is why we need Kerr out in the open as he holds the key to FRU operations in Northern Ireland which have never been admitted. He needs to explain the operations he ran, how he ran them, the soldiers he used, the IRA volunteers he used, and how it all contributed to the war.

‘We need to find out what he did, how he saw his role, what orders he gave, who did he report to, and what did he say to whoever he reported to. He needs to be asked did he know of the existence of Stakeknife, what did Stakeknife’s handler tell him in briefings and what was Stakeknife told by his handler. At the end of the day, people were getting murdered.

‘Kerr has a lot of questions to answer. The FRU wasn’t a rogue unit, and Kerr was not rogue. He was a soldier working under political orders and we need to establish who was giving him orders.

‘Kerr ran an organisation where British soldiers were running agents and those agents were killing people. A terrorist cannot pretend to be a terrorist - they need to act like one in order to maintain their cover. My concern is that operations by British military intelligence units like the FRU led to deaths in Northern Ireland through collusion between the security forces and terrorist organisations.’

Carlin fears that Kenova may prove fruitless due to non-cooperation of witnesses and suspects. ‘If we never question Kerr we will never get the truth about the Dirty War, and we need to get to the truth so we can achieve justice for the families of victims,’ he said.

A high level security source told the Herald on Sunday that ‘Kerr will be absolutely dealt with’. The source said that he would be interviewed by Kenova detectives under caution, and added: ‘However, whether he actually says anything is another matter. A lot of people when they are spoken to under caution elect not to say anything.’

The Kenova team has already interviewed a number of republicans, soldiers and police. It is headed by Chief Constable Jon Boutcher of Bedfordshire Police. The Chief Constable of Police Scotland, Iain Livingstone, sits on the independent steering group of Operation Kenova.