France will create 1,500 new places in its jails to isolate Islamist extremists and prevent them from converting other prisoners, the prime minister announced as he unveiled a major new plan aimed at stopping young people becoming terrorists.
“Islamist radicalisation is a menace for our society,” said Edouard Philippe, unveiling the plan that includes measures on dealing with the hundreds of French men and women - and their children - who have returned from the battlefields of Syria and Iraq or are expected to do so.
School teachers will get more training on how to spot signs that their pupils are becoming radicalised, and local authorities will be told to improve their scrutiny of the small but growing number of private Islamic schools.
Mr Philippe travelled along with a dozen government ministers to the northern city of Lille to present the programme which comprises a total of 60 measures and puts the emphasis on prevention.
The plan is the third programme in less than four years to try to prevent and control the phenomenon, which many other European states are also grappling with, of disaffected young people turning to radical Islam and sometimes to terror.
It aims to draw lessons from past failures, after three years that saw a wave of terror attacks claimed by the Islamic State of Iraq and the Levant (Isil) across France.
"This is a plan of mobilisation,” said the prime minister. “It's a battle the state alone cannot fight."
The new plan involves prisons, schools, social workers and the sports world, among others, on local and national levels.
"No one has a magic formula for 'deradicalisation' as if you could de-install dangerous software," said Mr Philippe. "But in France and elsewhere there are good approaches to prevention and disengagement."
A total of 512 people are currently serving time for terrorism offences in France and a further 1,139 prisoners have been flagged as having been radicalised.
The Prime Minister said he would create 1,500 places in separate prison wings for radicalised inmates, with 450 of them to be ready by the end of this year.
He also announced plans for three new centres that will attempt to reintegrate radicals referred by French courts, including jihadists returning from fallen Isil strongholds in Syria and Iraq.
A first de-radicalisation trial ended in failure last July, when a centre in western France that operated on a voluntary basis closed its doors after less than a year due to a lack of volunteers.
Other measures include setting up psychological care for returning children of French jihadists. So far 68 children have been repatriated, most of them under 13.
A total of 323 French nationals, including the 68 children, have returned to France from the Middle East. A further 1,180, including around 500 children, are still there.
French teachers will also be given more training to help them detect early signs of radicalisation and to debunk conspiracy theories.
Another measure will make it easier to reassign civil servants who show signs of radicalisation to jobs that do not involve contact with the public.