A former senior British officer has alleged that UK special forces committed “war crimes” in Afghanistan by carrying out the extrajudicial killing of detainees. He said that senior military officials were aware of the incidents but concealed them.

The comments emerged as part of a public inquiry launched by the UK Ministry of Defence after a BBC investigation reported that members of the Special Air Service (SAS) had killed 54 people under suspicious circumstances during a six-month deployment roughly a decade ago.

The inquiry is examining a series of night raids conducted between mid-2010 and mid-2013, when British forces were operating under the US-led coalition against the Taliban and other insurgents. Although British military police previously investigated allegations of wrongdoing including some involving the SAS, the Ministry of Defence has said those probes did not uncover sufficient evidence to prosecute.

The current inquiry is tasked with determining whether credible information about extrajudicial killings existed, whether military police investigations were properly conducted, and whether any unlawful killings were covered up.

Sir Charles Haddon-Cave, the inquiry’s chair and a senior judge, said it was essential both to hold accountable anyone who broke the law and to clear the names of those who did not.

In newly disclosed confidential testimony released on Monday, a former British officer who served as deputy chief of staff for UK special operations in Afghanistan said the number of enemy fighters reported killed in action consistently exceeded the number of weapons recovered. He said repeated claims that detainees had attempted to seize weapons or detonate grenades after being captured did not appear credible.

He told Oliver Glasgow, the inquiry’s lead counsel, that the incidents amounted to “war crimes,” describing detainees being taken back to raid sites and executed under the pretence that they had attacked British forces.

The officer said he raised his concerns at the time with the commander of UK special forces in Afghanistan, but instead of initiating an investigation, the commander ordered only a review of operational tactics.

He said he regretted not reporting the matter directly to military police, although he eventually did so in 2015. He also suggested the issue was not confined to a few soldiers but appeared more widespread, saying many within the special forces community seemed to know what was happening.

He added that the killing of detainees including, in some instances, toddlers shot in their beds was “not special, not elite, not what we stand for,” and that most personnel would not condone or cover up such actions.