Police have shut down a suspected radical mosque east of Paris, the third to be closed since France declared a state of emergency after last month's Paris attacks.
Interior Minister Bernard Cazeneuve said "three pseudo-cultural associations" linked to the mosque at Lagny-sur-Marne were also being dissolved, the first time the government has used its special powers to wind up such groups.
Two other mosques were closed last week at Gennevilliers in the northern suburbs of Paris and in the small town of L'Arbresle near the central city of Lyon.
The closures are part of a huge security crackdown after 130 people were killed in the jihadist attacks on Paris on November 13.
"Such measures to close mosques because of radicalisation have never before been taken by any government, including during the last state of emergency in 2005" after rioting broke out across France's troubled suburbs, Cazeneuve said in a statement.
He said a nine-millimetre revolver had been discovered during the raid in which one of the "leaders" of the Lagny-sur-Marne mosque was arrested. Investigators also found an illegal madrassa, or koranic school, and a hidden computer hard disk.
Nine people have since been placed under house arrest and 22 banned from leaving the country, the minister added.
The assets of imam Mohamed Hammoumi, who ran the mosque and the cultural associations until he left to live in Egypt in 2014, were frozen in April.
Authorities said on Wednesday the prayer room in L'Arbresle had been used by extremists suspected of having contacts with others in Syria.
Cazeneuve later told parliament that there had been 2235 searches leading to 263 arrests since the three-month state of emergency began.
"In 15 days we have seized a third of the weapons of war we would normally recover in a year," he said.
Of the 334 firearms seized, 145 were rifles and 34 assault weapons.
Cazeneuve said 330 people "who had been under surveillance by the security services for links to radical Islam have been put under house arrest."