The Beth Yossef school in Bussieres, around 60 kilometres east of the capital, was hosting “many underage American and Israeli children who do not speak French in abusive conditions”, said Laureline Peyrefitte, prosecutor in nearby Meaux.
The children, aged 12 and above, allegedly suffered “being locked up, confiscation of their identity documents, poor conditions, acts of abuse, lack of access to education and healthcare, and no possibility of returning to their families,” she added.
Authorities in the Seine-et-Marne department said in a statement that the children were placed in temporary care after being removed from the school, set apart from the village on its own grounds.
Police are also holding 16 of the school’s staff.
An American boy escaped from the school in July and sought shelter at the US embassy in Paris.
Others followed, and Israeli public television has been investigating the school for months.
“We found ourselves with around 30 witness accounts dating back to the 2000s from former pupils saying they suffered violence,” documentary filmmaker Dubi Kroitoru told AFP.
The journalists sent all their information to French police in July.
To relatives, “it seemed like the Harry Potter school, out in the green spaces,” said Jerusalem resident Rivka Azoulay, 26, whose 13-year-old brother had started at Beth Yossef just last week.
In conversations from a payphone at the school, the boy had so far seemed “happy”, Azoulay added, complaining that the French authorities had not been in touch with families.
France’s chief rabbi Haim Korsia told AFP: “It’s unacceptable for children’s lives to be put in danger, the charges are terrible.”
“The conditions they were living in are unacceptable, full stop,” he added.