PARIS (AP) -- France is cracking down on youth who leave their homes to fight with Islamist radicals in Syria's civil war.

The interior minister announced a series of tough love measures Wednesday that range from allowing suspicious parents to tip off authorities to withdrawing passports and putting potential jihadis' names in a European computer bank.

More youth from France are thought to have embarked on journeys to Syria than from any other European country, but the problem - and the risks of terrorism by those who return - is Europe-wide.

Foreign Minister Laurent Fabius said this week that 500 had gone to Syria from France, double the figure given in January. Children as young as 15 have made their way to jihadi training camps. Some have been fetched by their parents and brought home to be charged.

"It's a global plan with repressive elements aimed at dismantling networks that expose our country to risks" along with preventive measures, Interior Minister Bernard Cazeneuve told reporters.

Syria's civil war has left 150,000 dead and forced millions to flee their homes and country since it began in March 2011.

The plan was laid out at the weekly Cabinet meeting.

Among preventive measures is an alert system for parents who feel their children are at risk of taking up jihad. Parents would directly contact the Interior Ministry, which would set in motion a local plan mobilizing social services and even the educational system. Cazeneuve did not elaborate and it was not clear whether teachers and parents would, ultimately, be spying on their students and children.

In addition, authorities will withdraw passports from individuals suspected of wanting to travel to Syria. Foreign residents will be "immediately expelled" if authorities have reason to believe they participated in terrorist operations, the minister said.

France, in conjunction with European partners, also plans to increase its monitoring of websites that post videos and other messages inciting jihadi activities. Cazeneuve said he has already traveled to Germany and Austria to coordinate and will shortly be in Britain for talks.