An independent Islamic boys' school where inspectors found a CCTV camera in toilets has been rated "inadequate".
Ofsted downgraded Darul Hadis Latifiah in Bethnal Green, saying pupils were not being "prepared for life in modern Britain".
Inspectors found "grimy" facilities and "inappropriate" literature.
The school, for boys aged 11 to 20, said it was "preparing a formal complaint" in response. It said the camera only viewed the "washing area".