SAS operatives secretly hunted down and killed two members of the Iran-backed gang responsible for executing six British military policemen in Iraq, according to claims published in a new book.

The deaths of the Royal Military Police personnel in June 2003, occurring in Majar al-Kabir just weeks after the fall of Saddam Hussein, represented the single largest loss of British military life to hostile action during the entire Iraq campaign.

For more than two decades, the widely accepted account was that the killers had crossed over the border into Iran and escaped accountability entirely. However, in the book "Blades" by Mark Nicol, SAS sources state that operatives tracked down and eliminated two of the men responsible.

According to the account, SAS soldiers returned to the Majar al-Kabir police station days after the attack, posing as mourning comrades of the fallen men to obtain the names of the perpetrators from local Iraqi officers. Yet, senior British commanders are said to have halted subsequent missions over concerns of provoking retaliation against troops in southern Iraq's predominantly-Shia region.

Reflecting on the operation in the book, an SAS officer described the pushback from leadership: "We couldn't believe how disinterested UK commanders were in finding those responsible. We just got on with it and got lucky. We got their names and went after the murderers. But the reaction from the hierarchy was: 'Stop, you're stirring up opposition to us.'"

The officer added that the remaining suspects continued to present an active danger: "Every one of those gang members posed a live threat to UK forces. We would have got them all given the chance. We flew back to Baghdad knowing more British troops' lives would be lost because of the reluctance of senior officers to confront the Iranian threat."

The six Red Caps killed were Sergeant Simon Hamilton-Jewell, 41, Corporal Russell Aston, 30, Corporal Paul Long, 24, Lance Corporal Ben Hyde, 23, Lance Corporal Tom Keys, 20, and Corporal Simon Miller, 21. They were executed inside the police station in Maysan province after an angry demonstration broke out nearby, minutes after local Iraqi officers abandoned the building.

For the families of the fallen soldiers, the disclosures have brought complex reactions. John Miller, father of Corporal Simon Miller, said: "This has been kept from us for 23 years. I can't believe we are hearing it now, from you. I am very pleased to hear two of them are dead. I hope the SAS soldiers emptied their magazines into them, as they did to our Si."

Mr Miller also expressed anger that the unit was prevented from pursuing the rest of the gang. "It is another sickening blow for the families that the SAS were stopped from hunting down the others. They got away with it. The SAS catching these guys was our best chance of justice," he said.

The relatives have consistently challenged a 2006 inquest ruling which determined the deaths were unavoidable, long alleging a government cover-up regarding the circumstances. Further compounding their grief, nine Iraqi police officers were awarded £800,000 in compensation in 2013 following allegations of mistreatment during efforts to identify the culprits.

The Ministry of Defence has offered its heartfelt sympathies to the families of the deceased, though it adheres to a strict convention of not commenting publicly on special forces operations. What we do not know is whether official inquiries will ever address the decisions taken by commanders at the time.

With families continuing to call for full transparency over how the mission was managed, I'll be following this one — check back for updates.