A minister has told an inquiry that he was angry with the former defence secretary Ben Wallace after discovering that UK special forces officers knew about Afghanistan death squad allegations before he described them as untrue in the House of Commons. Johnny Mercer wrote to Wallace in August 2020 shortly after emails surfaced in the Sunday Times that showed senior special forces officers expressed serious concerns about the killings of 33 people in 11 night raids in the war-torn nation in 2011. In the letter, shown to the Afghanistan inquiry on Wednesday, Mercer told Wallace it was “completely unacceptable” that he had been allowed to make statements to the Commons in January 2020 when people knew them to be “incorrect”. Mercer, the minister for veterans’ affairs, told the inquiry he was angry that the director of special forces, the chief of the general staff and the defence secretary had “not done their job that was incumbent upon them with their rank and privileges in those organisations”. He described his time working under Wallace as “very difficult”, adding: “I did not enjoy it and it placed me in a number of very, very uncomfortable positions.” The inquiry will examine whether the SAS had a policy of executing males of fighting age who posed no threat in Afghanistan between 2010 and 2013. Afghan families have accused UK special forces of conducting a “campaign of murder” against civilians, and claim senior officers and personnel at the Ministry of Defence “sought to prevent adequate investigation”. In his letter to Wallace in August 2020, Mercer wrote: “That I have been allowed to read out statements to the House of Commons that individuals in strategic appointments in the department knew to be incorrect is completely unacceptable. These were clearly not complaints by a ‘small number of individuals within the investigations team’ but widespread. “I have continually downplayed these allegations in public, too, to support UKSF1 [the SAS] and the department. That was clearly a mistake.” Mercer told Wallace he wanted to formally request an opportunity to correct the record in the Commons. Ending the letter, Mercer said: “Finally, this whole episode makes me very sad. I, like you, have dedicated my political career to improving the lot of those who serve, both currently and veterans. “I repeatedly warned against the outcome and yet it has happened, and I have suffered significant reputational damage in my pursuit of ending vexatious claims that have ruined the lives of so many of our finest people. I will continue in this pursuit but this boil must be lanced and I can never be put in this position again.” Asked by Oliver Glasgow KC, counsel to the inquiry, what the boil that must be lanced was, Mercer said: “The allegations concerned with this inquiry.” Mercer said he raised his concerns about being kept in the dark with Wallace and the chief of the defence staff on the phone while away on holiday in France. He told the inquiry: “So there were two issues – one was it was completely unacceptable that I’d asked to see this information and the first I read about it was in the Sunday Times. Secondarily, I was very cross that I had been allowed to make a statement in the House of Commons in January that year that was clearly incorrect when faced with the evidence that existed within my own department – and for me that was a kind of red line being crossed, in terms of ‘we’re not on the same side here’.” Glasgow asked: “So, in effect, the concerns as you explained them – you were, would it be fair to say, angry that you had not been told the true picture?” Mercer replied: “Mr Glasgow, I don’t disguise the fact that I am angry with these people. The fact I’m sat here today going through this is because they have not done their job that was incumbent upon them with their rank and privileges in those organisations – and yes, I’m angry about that.” Glasgow continued: “And when you say them, can you tell us who those individuals are?” Mercer said: “Senior leaders within the Ministry of Defence and within UK special forces.” The minister went on to confirm that two of the individuals were the director of special forces and the chief of the general staff. Glasgow went on: “Secretary of state?” Mercer said: “Yeah, my time in that department was very difficult, I did not enjoy it and it placed me in a number of very, very uncomfortable positions.” Two Royal Military Police investigations, codenamed Operation Northmoor and Operation Cestro, are due to be scrutinised by the inquiry. No charges were brought under Operation Northmoor, a £10m investigation set up in 2014 to examine allegations of executions by special forces, including those of children. In Operation Cestro, three soldiers were referred to the Service Prosecuting Authority but none were prosecuted. The inquiry continues.