At least a quarter of suspected illegal schools were found in London, putting thousands of children’s education at risk in the capital.
A taskforce set up by Ofsted chief inspector Michael Wilshaw found that around 25 unregistered schools were operating in London, with more than 100 found across England.
The team of seven inspectors have been carrying out visits to the establishments since January, working closely with the Department for Education (DfE), which last month saw warning notices issued to seven suspected illegal schools, including at least one in London.
Although west London can boast a high standard of schools in many areas , children’s charity NSPCC has spoken out about the possible safety concerns for children attending these type of schools and how some parents are unaware of the existence of such schools.
An NSPCC spokesman said: "These illegal schools are troubling because parents cannot be certain that employees at these institutions have passed rigorous, robust, checks that make a child’s safety the top priority.
"When picking these institutions, some parents might not know that such ‘schools’ are unregistered and employees haven’t had the proper background checks or safeguarding training, and are unaware of the risks these pose to their children.
"It’s vital that every individual who works with children passes these checks to help keep every child safe."
The dangers of unregistered school pose a conundrum for parents in west London under pressure to get their children into good schools, with a report at the start of this year revealing some faced the likelihood of missing out on their chosen schools if they lived more than 300 metres away from it .
'Significant risk of harm and indoctrination'
Unregistered schools operate outside of direction from the local authority, Oftsed and DfE.
In a letter to Education secretary Nicky Morgan, Mr Wilshaw said: “What we have found so far is likely to represent only a small proportion of the illegal schools operating across the country.
“Inspectors are hearing about suspected new cases every week.
“I therefore remain extremely concerned about the number of children and young people attending these schools who may be at significant risk of harm and indoctrination.”
The letter also highlighted alarming safety concerns, such as fire hazards including inaccessible fire escapes; unhygienic premises, in one case chemistry equipment in an unlocked food cupboard in a room where children ate their lunch; and staff and volunteers not being cleared to work with children.
In February, getwestlondon reported that schools in Hillingdon were being challenged by the council to raise their game, amid accusations of a "lack of ambition" .
Last week, a mother spoke of her nightmare as her young son was found outside an Eastcote nursery , having escaped unnoticed by staff.