French police have conducted a series of raids targeting Islamist networks, three days after the beheading of a history teacher who had shown his pupils a cartoon of the Prophet Mohammed.
Interior Minister Gerald Darmanin vowed there would be "not a minute's respite for enemies of the Republic", after tens of thousands took part in rallies countrywide on Sunday to honour teacher Samuel Paty and defend freedom of expression.
A silent rally was planned on Tuesday evening, as well as a ceremony on Wednesday at the Sorbonne attended by President Emmanuel Macron.
Fifteen people have been detained so far, including four pupils who may have helped the killer - an 18-year-old of Chechen origin who was killed by police -- to identify the teacher in return for payment.
Law enforcement carried out 40 raids on Monday, mostly around Paris, with many more planned.
"We want to harass and destabilise this movement in a very determined way," one ministry source said.
Darmanin said the government would also tighten its grip on institutions and charities with suspected links to Islamist networks.
to receive the information you want in your inbox. Special newsletters are available to subscribers.