French authorities will search and potentially close dozens of mosques suspected of separatism as part of a campaign to combat extremists after a spate of attacks.
Interior Minister Gerald Darmanin sent a note to regional security chiefs listing 16 addresses in the Paris region and 60 others around the country.
He later described the operation as a “massive and unprecedented action” against separatism in France, which is home to the largest Muslim population in western Europe.
He told Le Figaro newspaper that authorities would "attack the breeding grounds of terrorism" – a reference to mosques promoting extremism.
The inspections follow the beheading in October of a teacher in Paris and the stabbing to death of three people in a church in Nice.
"Seventy-six mosques are now suspected of separatism," Mr Darmanin tweeted.
“In the coming days, checks will be carried out on these places of worship. If ever these doubts are confirmed, I will ask for their closure.”
He told RTL that the fact only a fraction of about 2,600 mosques in France were suspected of peddling radical theories showed "we are far from a situation of widespread radicalisation".
“Nearly all Muslims in France respect the laws of the republic and are hurt by that [radicalisation],” he said.“There are 2,600 Muslim places of worship so 76 out of 2,600 is far from a generalised radicalisation we can hear about sometimes,” he said. “But some places of worship are manifestly anti-republican.”
The killing of teacher Samuel Paty, who showed pupils cartoons of the Prophet Mohammed in a class on free speech, sent shock waves through France, where some considered it an attack on the secular republican values the French hold dear.
After his murder the authorities raided dozens of Muslim sports groups, charities and associations suspected of promoting extremism.
They also ordered the temporary closure of a mosque near Paris that shared a vitriolic video inciting hatred against Paty.
In October, French President Emmanuel Macron announced that the government would draft a new law to tackle separatism and said there would be strict controls on religious groups and a ban on home schooling.
A pro-ISIS media group said the attack in Nice was revenge for Mr Macron's plans.