Ministers have been accused of covering up evidence for months about crumbling concrete at a Scottish school, which led to the rushed decision to close more than 100 other schools. Decay in aerated concrete in a building at Queen Victoria school, a privately run boarding school in Perthshire, was seen as so significant that Department of Education (DfE) officials sent health and safety officials to examine it in May. But Scottish government sources said they were told only on Thursday about the discovery. They allege the DfE refuses to disclose the expert evidence about what it discovered, despite repeated requests from Jenny Gilruth, the Scottish education secretary. Whitehall sources said the findings at the school helped trigger the dramatic warnings in England last week that hundreds of school buildings that used reinforced autoclaved aerated concrete (Raac) were at risk of collapse. Gillian Keegan, the UK education secretary, told Jeremy Vine on BBC radio this week she had to take action after three incidents during the summer involving Raac. She admitted that making the closure decision at the end of August was “the worst time”, adding: “I am very sorry about the timings but I 100% think it was the right decision.” The disclosure that the UK government found “worrying” evidence in May will raise further questions about why it took so long to change the status of more than 100 schools in England to “critical”. The Queen Victoria is a military school fully funded by the Ministry of Defence and overseen by a UK government-appointed charitable board. Coeducational, it specialises in schooling the children of armed forces personnel. In April, “concerning” evidence of decay was found in an auxiliary building built with Raac, sources said. That was passed to the DfE in May, which sent health and safety experts to examine the structure, which was immediately taken out of use. Whitehall sources said the findings from the Queen Victoria and from inspections at two other schools in England were so alarming it led the UK government to change its stance on the safety of Raac. Even so, DfE officials waited until Thursday last week before telling Scottish ministers about the inspection in May and alerting them to its findings, according to sources at Holyrood. Those sources said Keegan then wrote to Gilruth to formally notify her on Saturday evening. The DfE has not yet shared its technical report on its findings, even though the Scottish government has legal responsibility for school safety and planning in Scotland, and for assessing a school’s performance. Gilruth is said to be furious about the delay and has written twice to Keegan asking the DfE to share its findings – first on Sunday and then on Tuesday afternoon. So far, Gilruth has only received photographs of the suspect wall. The Raac crisis has affected 35 primary and secondary schools across Scotland, with some buildings shut over safety concerns, and councils facing multimillion pound repair bills. Pupils and staff at some sites have been forced to use portable classrooms or other venues, or revert to online learning strategies developed during the Covid pandemic, and some PE blocks and ancillary rooms have been closed. One school in West Lothian was closed in November last year, and children sent to nearby primary schools while Raac panels were replaced. Two primaries in Edinburgh have closed classrooms while remedial work is undertaken. Inspections have been under way since 2018, and experts said disruption was likely to be minimal. The row follows similar complaints from the Welsh government earlier this week that the DfE first alerted it about the perceived risks posed by Raac at 6.57pm on Sunday evening, on the eve of the new school term in Wales. Jeremy Miles, the Welsh education minister, said that delay was “hugely regrettable“. It forced the immediate closure of two schools in Anglesey (Ynys Môn) in north Wales. The DfE did not dispute the Scottish government’s account of its handling of the findings, but insisted the UK government had been liaising closely with all the UK’s devolved administrations about the general issues with Raac concrete.