Ofsted inspectors gave Darul Uloom Islamic High School in Birmingham an unexpected visit after having formerly rated the school as “inadequate”.
Inspectors said that the pupils of the school were not being protected from “extreme views”.
The school overruled former Ofsted criticism, saying that it endorsed “both Islamic and British values”.
However, a Spokeswoman for the Department for Education said: “The allegations will be urgently investigated and action will be taken against schools promoting twisted ideologies.”
She added: “These leaflets should have no place in any school – and we will not hesitate to take strong action when schools focus on ideological indoctrination rather than a high-quality education.”
An Ofsted inspection last year found numerous flaws with the school and inspectors returning without warning to monitor how the plans for improvement were being instigated.
But instead of finding a good change, the inspectors found published material with “extremist views”.
A huge number of leaflets that contained enormously concerning and extremist views such as “music, dancing and singing are acts of the devil and are prohibited” which were discovered during the inspection.
“The leaflets were found in areas shared by the school and adjoining mosque which are used by leaders and in areas used by the pupils from the school,” said the Inspectors.
Ofsted says that it is not clear who created the leaflets, but they appeared to be calling for a boycott of a local music festival.
The leaflet made reference to music in terms of “public indecency” and the “proliferation of sinful activities”.
A Department for Education Spokeswoman said: “Extremism has no place in our society and when we find schools promoting twisted ideologies we will not hesitate to take action, including closing the school or working with the police if necessary.”
