Ofsted has sounded a fresh warning of the risks to children educated in unregistered schools after revealing it has investigated more than 500 cases over the past three years.
The inspection service said it had investigated 521 settings between the beginning of January 2016 and the end of December last year and carried out inspections on 259 of them.
It inspected 18 Jewish, 36 Muslim and 12 Christian settings, while the remaining 193 were not of any faith or of unknown religious character.
But it gave no religious breakdown of the 71 settings issued with warning notices - of which 15 closed.