A man who beheaded a history teacher outside Paris last week had been in contact with a parent leading an online campaign against the teacher, the investigation into the killing revealed on Tuesday.
The breakthrough in the case of the brutal murder of school teacher Samuel Paty came as President Emmanuel Macron promised more pressure on Islamist extremism after days of clampdowns which have resulted in over a dozen arrests, a mosque ordered shut and a pro-Hamas group to be dissolved.
"Our fellow citizens expect actions," Mr Macron said during a visit to a Paris suburb. "These actions will be stepped up."
Police sources said earlier that the 18-year-old killer had exchanged messages on WhatsApp with the man who wanted Samuel Paty fired after his daughter told him how the teacher had shown cartoons of the Prophet Mohammed in a lesson on free speech.
The parent, the father of a girl in Mr Paty's class, was behind an online campaign urging "mobilisation" against the teacher.
French President Emmanuel Macron delivers a speech at the end of a visit on the fight against separatism in Paris. Source: AFP
'Not a minute's respite'
The man, now in police custody, had placed his phone number on Facebook and exchanged messages with the killer, 18-year-old Chechen Abdullakh Anzorov, on WhatsApp in the days leading up to the murder, police sources told AFP.
Anzorov was shot dead by police soon after the killing.
Among other messages, the father had published a video railing against Mr Paty's choice of lesson material.
The mosque, now targeted for a six-month closure, shared this video on its own Facebook Page.
Mr Macron added that a pro-Hamas group active in France would be dissolved for being "directly implicated" in the murder of the teacher.
The decision to shut down the "Cheikh Yassine Collective", which supports the Palestinian cause and is named after the Hamas founder, will be taken at Wednesday's cabinet meeting, he said.
The group's founder and Islamist radical, Abdelhakim Sefrioui, is currently being held by police for publishing a video on YouTube insulting Mr Paty.
Prime Minister Jean Castex told MPs on Tuesday that the government was now targeting "all associations whose complicity with radical Islamism has been established".
Mr Paty, 47, was attacked Friday on his way home from the junior high school where he taught in Conflans-Sainte-Honorine, 40 kilometres northwest of Paris.
Police have arrested 16 people in connection with the killing, including and four members of Anzorov's family.
Interior Minister Gerald Darmanin vowed there would be "not a minute's respite for enemies of the Republic".
Online campaign
Education Minister Jean-Michel Blanquer said Tuesday that Mr Paty would be posthumously bestowed France's highest order of merit, the Legion of Honour.
The school said Mr Paty had given Muslim pupils the choice to leave the classroom before he showed the cartoons.
But the girl's father was outraged by him displaying a caricature of the prophet naked, and sought Mr Paty's dismissal for disseminating "pornography".
On Tuesday, the head of the Pantin mosque, M'hammed Henniche, said he had shared the father's video out of fear that Muslim children were being singled out in class.
Five pupils suspected of accepting payment for pointing Mr Paty out to his killer were among those in police custody.
Imam of Drancy Hassen Chalghoumi and Jewish writer Marek Halter attending a gathering of imams outside the Bois d'Aulne secondary school outside Paris. Source: ABACA
'The decapitated Republic'
Mr Paty's beheading was the second knife attack claimed in the name of avenging the Prophet since a trial started last month over the Charlie Hebdo killings in 2015 when 12 people, including cartoonists, were gunned down for publishing Mohammed cartoons.
After Mr Paty's murder, Mr Macron threatened that "fear is about to change sides".
Junior interior minister Marlene Schiappa assembled French bosses of social networks on Tuesday to discuss bolstering the "fight against cyber-Islamism".
Tens of thousands of people took part in rallies countrywide over the weekend to honour Mr Paty and defend freedom of expression.
The French parliament observed a minute of silence for Mr Paty on Tuesday, while thousands gathered for a silent march in the teacher's honour in Conflans-Sainte-Honorine in the evening.
Mr Macron will attend an official homage with Mr Paty's family on Wednesday at the Sorbonne university.
Mr Darmanin has called for vigilance at schools to be bolstered when pupils return after the autumn break.
The next edition of Charlie Hebdo, meanwhile, will feature the headline "The decapitated Republic" on its front page along with cartoons representing various professions, the weekly said on Tuesday.
"These murderers want to decapitate democracy itself," reads the editorial to be published Wednesday.
