Paris (AFP) - Six French citizens have had their passports confiscated and 40 more will be banned from leaving the country as Europe cracks down on would-be jihadists planning to travel to Syria and Iraq.
This is the first time France has resorted to the measure since its introduction as part of a raft of new counter-terrorism laws in November.
"If French people go commit attacks in Iraq or in Syria, on their return they will present an even greater danger of carrying out large-scale terrorist attacks on the national territory," Interior Minister Bernard Cazeneuve told reporters.
"There are currently six administrative bans on leaving the country that have already been signed, and around 40 that are being prepared," he added.
The passports and identity cards of those targeted -- men and women aged between 23 and 28 -- have been confiscated for six months, after which the order can be renewed.
Such efforts are being mirrored across Europe after hundreds have travelled to the Middle East to join jihadist groups such as the Islamic State and Al-Qaeda-linked Nusra Front in recent years.
Jihadist attacks in Paris and Copenhagen this year have further focused minds.
Denmark recently passed a law, which is to come into force on March 1, allowing travel bans and the removal of passports from those suspected of seeking to join terrorist groups.
Britain, where the government says some 500 people have already travelled to join jihadist groups, has already confiscated dozens of passports.
The government has not given up-to-date figures but admitted in November that it had withdrawn 24 passports, and has since updated its laws to make the process easier and allow for people to be temporarily banned from re-entry to the UK.
- Support from Brussels -
The EU's counter-terrorism chief Gilles de Kerchove last month called for more information-sharing across the continent and closer screening of travellers.
"We need to modify the border rules for the Schengen area, so as to systematically control all entries and departures by European citizens," he told AFP.
But news that three teenage girls last week fled their London homes and were possibly on their way to Syria via Turkey have shown the difficulty of identifying would-be jihadists.
The three girls were friends with another student at their school who left for Syria in December and had been questioned by staff, but were not thought to have been radicalised.
The clampdowns on travel have drawn flak from human rights groups, who question the legality of restricting people's movement before any crime has been committed.
UK-based rights group Liberty released a statement last year saying new counter-terror legislation "plays into the hands of terrorists by allowing them to shape our laws in a way that undermines our principles."
In France, Cazeneuve has highlighted his ministry's efforts to set up a warning system through which friends and family can alert authorities about potential jihadist cases.
He said the ministry had been alerted to over 1,000 cases and that "several dozen" planned trips to Syria and Iraq had been prevented as a result.
Cazeneuve has also been in California in recent days, meeting with major internet firms in a bid to improve information-sharing about online jihadist networks.
The minister is due to meet again with internet company bosses in Paris in early April, he said.
Some 1,400 people living in France have either joined the jihadist cause in Syria and Iraq or are planning to do so, Prime Minister Manuel Valls said last month.