An investigation into the attack has revealed that a man who killed a history teacher in France last week was linked to parents leading an online campaign against the teacher.

The turning point in the case comes after President Emmanuel Macron promised to put more pressure on Islamic extremism. More than a dozen arrests were made, and a mosque was ordered to close and a pro-Hamas group disbanded.

“Our fellow citizens look forward to action,” Macron said during a visit to the outskirts of Paris. “These activities will increase.”

47 years old Samuel Patty was beheaded on the way home from the secondary school he taught. 40 km (25 miles) northwest of Paris on the Confluence-Saint-Honorine.

The teacher commented on how the cartoons of the Prophet Muhammad were shown after his daughter told him that Samuel Patty should be fired for sending messages on WhatsApp to an 18-year-old killer.

The parents of a girl in Mr. Patty’s class were behind an online campaign urging them to “mobilize” against the teacher.

The man, who is now in police custody, posted his phone number on Facebook and exchanged messages on WhatsApp with his killer Chechen Abdullak Ansorov in the days leading up to the murder.

Ansorov was shot dead by police shortly after the murder.

A photo of the teacher and a confessional message were found on his mobile phone.

Sixteen people have been arrested in connection with the murder. And four members of Ansorov’s family.

Among those arrested were five students suspected of accepting money for pointing Mr Patty to the killer.

The father, who led the online campaign, published a video protesting Patty’s choice of lessons.

The church, which is aiming for a six-month closure, shared the video on its Facebook page.

President Macron has said he will disband the pro-Hamas group “Czech Yassin Collective” active in France for his direct involvement in the teacher’s assassination.

Police have arrested Abdulhakim Sefrioi, the group’s founder and Islamic extremist, for posting a video insulting Mr Patty on YouTube.

French Prime Minister Jean Costex told MPs that the government was targeting all associations that collaborated with extremist Islamists.

Education Minister Jean-Michel Blanker has said that Patrick will be awarded France’s highest honor, the Legion of Honor, posthumously.