Teachers at a Nottingham special school locked pupils in classrooms to stop them running out of classes, according to a report by Ofsted.
Woodlands School, in Beechdale Road, Aspley, Nottingham, was put into special measures following an inspection in June.
A report published by Ofsted last week said the school, which has 56 pupils aged 3-16, did not adequately safeguard pupils because some classroom doors were "locked inappropriately" when the children were in the room to stop them from running out.
Inspectors said the practice had been condoned by on-site leaders and had not been picked up by the governing body or the executive headteacher.
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Another very cold and frosty start on Sunday. Staying dry, with plenty of sunshine once again. Feeling very cold with stiff easterly wind.
Largely sunny, with only patchy cloud. However it will still feel bitterly cold, despite the wind easing a little.
The Royal Marines received the Freedom of the City of Birmingham during a special ceremony in Victoria Square today.