Progress is being made in the investigation into the activities of the British army’s IRA agent Stakeknife, the English police officer leading the inquiry said on Monday.

Bedfordshire chief constable Jon Boutcher is heading the Operation Kenova investigation into the activities of the agent, codenamed Stakeknife, who has been named as west Belfast man Freddie Scappaticci.

It is alleged that Stakeknife was involved in 24 to 50 murders and possibly more and that some of his victims were allegedly sacrificed by his handlers to protect his identity.

Scappaticci has denied he was a British agent within the IRA. Stakeknife is alleged to have committed most of the killing when he was in charge of the IRA’s internal security department who checked for informers, its so-called “Nutting Squad”.

Mr Boutcher urged anyone with information about the “allegations of murder and torture by alleged army agent Stakeknife” to bring it forward to his team of detectives.

“This is a complex investigation. However we are making progress gathering evidence; some of the statements made by families have been incredibly moving and I would like to thank all of those we have spoken to so far for speaking out,” said Mr Boutcher.

“There would have been those who played a role on the periphery of the offending - they might have housed people involved or held weapons which may have been used,” he explained. “We want to speak to each and every person who played a part in any of these crimes to ultimately get to the truth for the families. I encourage people to come forward, you will be treated sympathetically.”

Mr Boutcher hoped that with the passage of time “since these offences occurred and the realisation that these cowardly crimes were not justified in any way will mean that misplaced loyalties will have changed and people will now feel strong enough to come forward”.

Freddie Scappaticci was named as Stakeknife in 2003. He initially denied the claims but then fled Belfast. He is now under British security protection. The media is not allowed to report anything that could suggest where he is living or to show images of what he now looks like.

Mr Boutcher made his appeal ahead of a BBC Panorama programme focusing on Stakeknife which is set to be broadcast on Tuesday, April 11th.

He urged anyone with any information to call the dedicated phone line 01234 858298 (from Republic 00 44 1234 858298) or email kenova@met.police.uk