France ordered the temporary closure of a mosque outside Paris on Tuesday, part of a crackdown on Muslims who incite hatred after the decapitation of a teacher who showed his class caricatures of the Prophet Mohammad.
The Grand Mosque of Pantin, a low-income suburb on the capital's northeastern outskirts, had shared a video on its Facebook page before the attack that vented hatred against history teacher Samuel Paty.
Police plastered notices of the closure order outside the mosque as the authorities promised a tough response against the disseminators of hate messages, preachers of radicalised sermons and foreigners believed to pose a security threat to France.
The six-month order was "for the sole purpose of preventing acts of terrorism", the notice issued by the head of the Seine-Saint-Denis department read.
The beheading of a public servant by a suspected Islamist for his use of religious satire to explore with students the debate surrounding freedom of expression, a deeply cherished tenet of democracy in secular France, has convulsed the country and shocked the world.
President Emmanuel Macron is increasingly concerned by what he calls Islamist separatism: the attempt by hostile elements within France's large Muslim community to impose conservative Islamic beliefs over the traditional values of the French Republic in some communities.
Interior Minister Gerald Darmain said this week France was confronted by an "enemy within".
The rector of the Grand Mosque of Panin, M'hammed Henniche, this weekend expressed regret over sharing the video on social media, after it emerged Paty had become the victim of a vicious online campaign of intimidation even before he was killed.
In the video, the Muslim father of one of Paty's students said the history teacher had singled out Muslim students and asked them to leave his class before showing the cartoons. He called Paty a thug and said he wanted the teacher removed.
Henniche told Agence France Presse he had shared the video, filmed by the father of a student at Paty's school, not to endorse the complaint but out of concern for Muslim children.
The student's father is now in police custody.
Calls by Reuters to the mosque on Tuesday went unanswered.
"There's no room for violence in our religion", the mosque said in a statement published on Facebook on Monday. "We strongly condemn this savagery."
One Pantin resident, who gave her name as Maya and said her husband prayed at the mosque, called the closure "sad for our community".