A UK spy codenamed Stakeknife, who operated within the IRA during the Troubles in Northern Ireland, cost more lives than he saved, according to a new report.

Army spy Freddie Scappaticci led the IRA’s Internal Security Unit – known as the “nutting squad” – but secretly worked for British intelligence services.

Defence chiefs previously defended Scappaticci, who was unmasked by the Sunday Herald in 2003, on the grounds his work saved hundreds of lives – but a new report published Friday "inherently implausible ... a comparison rooted in fables and fairy tales”.

He was linked to 18 murders of IRA members accused of being informers and the “nutting squad” he was in charge of was responsible for 30 deaths overall.

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The interim findings of Operation Kenova examined 101 murders and abductions linked to the Internal Security Unit of the IRA.

It does not name Scappaticci as Stakeknife, citing the the Government’s policy of "neither confirm nor deny", but it does confirm the agent was one person rather than a name for a group of people. 

Jon Boutcher, the Chief Constable of the Police Service of Northern Ireland, said he estimated the number of lives saved as a result of intelligence provided by Stakeknife was in the high single figures or low double figures and “nowhere near” the hundreds that have been claimed.

The National: Freddie Scappaticci (far left) pictured at the 1988 funeral of IRA man Brendan Davison Freddie Scappaticci (far left) pictured at the 1988 funeral of IRA man Brendan Davison (Image: Pacemaker)

“Crucially this is not a net estimate because it does not take account of the lives lost as a consequence of Stakeknife’s continued operation as an agent,” he added.

“And, from what I have seen, I think it probable that this resulted in more lives being lost than saved.

“Furthermore, there were undoubtedly occasions when Stakeknife ignored his handlers, acted outside his tasking and did things he should not have done and when very serious risks were run.”

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The £40 million probe, led by Bedfordshire Police for the last seven years, found that  Stakeknife was involved in “very serious and wholly unjustifiable criminality, including murder”.

He said a lack of legal framework to govern the use of agents during the Troubles created a “maverick culture” where agent handling was considered a high stakes “dark art” that was practised “off the books”.

Both the UK Government and the Republican leadership have been urged to apologise to the families of those who lost loved ones suspected of being state agents during the Troubles.

Boutcher paid tribute to the families impacted by the Kenova investigation.

“Many of these families have endured delays, setbacks and unfulfilled promises in their quest for the truth,” he said.

“Their strength, determination and dignity over the many years is the most inspirational aspect of legacy and a lesson to all of us”.

Stormont Justice Minister Naomi Long said: “I welcome the publication today of the Operation Kenova interim report.

“Investigating legacy issues can be very challenging and time consuming for all involved and can be painful and distressing for those directly affected.

“This has been a long and difficult journey for those families seeking the truth about what happened to their loved ones.

“I sincerely hope that today brings some measure of comfort for them and that they find some value in the interim report. No doubt everyone involved will wish to take time to fully understand the contents and any associated implications for them.”

The UK Government was approached for comment.