A letter outlining a plot by some Muslims to take over schools in Birmingham was "no hoax", according to the city's education commissioner Sir Mike Tomlinson.
The anonymous Trojan Horse letter, discovered in 2013, included advice on installing school governors.
It has been the subject of four major inquiries.
Sir Mike said he believed many details in the letter "were happening [in schools], without a shadow of doubt".
The letter outlined a plan to bring in new school governors, undermine head teachers and ultimately introduce changes sympathetic to the group of conservative Muslims.
"Whatever anybody says, it was no hoax," Sir Mike said.
He said evidence uncovered in inquiries by the Department for Education (DfE) and Ofsted "mirrored what was said in the letter". [BBC] Read more
