PARIS (AP) -- The longer that France's military intervention goes on in Mali, the greater the risk that homegrown Islamic militants will organize to plot attacks back in France, a top French counterterrorism investigator told The Associated Press.
Investigating Judge Marc Trevidic said young radicals in France see the Paris government as enemy No. 1 in the "new jihad" and consider France's intervention in Mali, which started last month to help the Malian government fight al-Qaida-linked militants, as an aggression against Islam. Small groups of France-based militants have already headed to Mali.
"The longer it goes on, things rot, the groups get organized, and the more networks constitute themselves. The longer it goes on, the more dangerous it grows," Trevidic said in an interview late Thursday. "The groups will need time to catch their breath, set up networks and possibly take action."
The investigating judge, who has been involved in some of France's biggest terrorism cases in recent years, spoke after diplomats and other French officials acknowledged to the AP this week that French forces are likely to remain in Mali at least through July.
President Francois Hollande and his major ministers have talked about a gradual pullout of the 4,000 troops now in Mali starting this month. But the combat in rugged Sahara Desert mountains is growing harder, and the threat is rising that the militants will turn to suicide attacks, hostage-takings and other guerrilla tactics.
Meanwhile, it's proving tougher to mobilize African troops to eventually take over the security lead from the French and to get European trainers on the ground to help better professionalize Mali's bedraggled soldiers.
Authorities in France for years have monitored radical Islamists -- many whose families hail from former French colonies in northern Africa -- who travel abroad to wage jihad, or holy war, and could return home with battle skills and know-how to carry out terrorist attacks.
But unlike Iraq, or the border regions of Pakistan and Afghanistan, which continue to draw some French militants, Mali and much of West Africa were once French colonies. Thousands of French and dual nationals reside there, do business and maintain family ties. And that makes it especially tricky to monitor suspect travelers.
Mali "is the fashionable jihad at the moment. ... In this new jihad, the enemy is clearly France," Trevidic said.
The 7-week-old French campaign, backed by Malian and other troops notably from Chad, has driven al-Qaida's affiliates out of the cities in northeast Mali that they controlled for 10 months. Now, French officials say, the hardest fighting is taking place where many insurgents have holed up in the Adrar des Ifoghas range along the extensive Algerian border.
Trevidic said French judicial cases involving Mali were first opened in June. Extremists took advantage of a power vacuum in Mali after a coup last year and started imposing harsh rule on cities across northern Mali.
"We noticed excitement from the moment that young French radical Muslims learned that Shariah law was being applied in north Mali," he said. Many French radicals with dual citizenship -- French-Malian, French-Nigerien, French-Nigerian, French-Congolese -- wanted to go.
About 15 people have traveled to the region, and a few have returned to France, Trevidic said. Legal cases have been opened involving about 10 people -- most of whom never left France but sent allies to Mali to join Islamic groups.
A challenge for French authorities is monitoring them to see if they plot attacks and not arresting them right away -- to solidify judicial cases against them -- and especially trying to "control" those who do return home to France.
The French military intervention that started Jan. 11 all but halted militants' departures toward Mali, Trevidic said. "For now, the situation is too tumultuous," he said. "We're in a bit of wait-and-see about what happens in the months to come."
Since the French air and ground campaign began, militants in France have lowered their profiles.
"Everybody ... has ducked. They're not getting noticed. A big problem in the current legal cases is when people in groups being monitored converse and have normal relations, and then suddenly cut all ties. They don't call each other, they stop seeing each other," Trevidic said.
"You think, 'it's because of the military action, it's hot, and they don't want to get noticed'," he added. "But it can also be worrisome, sometimes, it could be a sign that they are getting close to an action."
"Maybe it will calm down, by some miracle. But it's all going to depend on the states involved and how they manage their own problems," he said. "If the French army leaves, will the Malian military be strong enough to thwart the counterattacks of the Islamists? For the moment, we don't quite have that impression."
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