Frankrike frykter at intervensjonen i Mali kan slå ut i terror på hjemmebane. Innenriksminister Manuel Valls sa tirsdag kveld at det er utplassert 700 soldater i og rundt Paris. Alarmnivået er hevet.

Spesialforhørsdommer Marc Trevidic sa det allerede var kartlagt islamister som hadde reist fra Frankrike for å slutte seg til jihadistene i Mali. Det er en broken gjeng av konvertitter og innvandrere.

Valls said everything possible was being done to ensure that did not happen, while cautioning that the threat posed by foreign and homegrown extremists had existed long before French forces went into action in the former colony.

«In terms of evaluating the risk, we have to be prudent. But our interior and exterior intelligence services are being extremely vigilant.

«The threat is not new but it is very strong and we have to be fully mobilised to meet it.»

France has not yet raised the level of its national anti-terrorist alert system to the «scarlet» level that was briefly applied last year when Islamist gunman Mohamed Merah went on a killing spree in and around the southern city of Toulouse.

Under the current «reinforced red» alert, France has stepped up security at all public buildings, railway stations and other transport facilities as well as at airports and nuclear power plants.

Special measures have also been put in place to deter potential attacks on the embassies of foreign countries that have backed France’s action, with US, British and Israeli interests deemed to be the most likely targets. Merah’s killing of a rabbi, three Jewish children and three French paratroopers and the dismantling in October of an Islamist «terrorist cell» have highlighted the extent to which France faces a homegrown threat.

Anti-terrorist judge Marc Trevidic said there had already been a trickle of French Islamists heading to Mali before France launched airstrikes on Friday.

Trevidic said there were currently four separate investigations into French-based militants who have travelled to meet or otherwise made contact with the Malian groups.

«There’s always one Malian involved but often it is groups made up of a patchwork of nationalities: French converts to Islam, people from across North Africa, Nigerians, Senegalese, etc…» he added.

«You can be sure that we have them under very close surveillance – the trick is not to pounce on them prematurely before we know what they are up to.»

Hamedi Diarra, a leader of the sizable Malian community in France, said he did not think his Islamist compatriots had the means to carry out attacks on French soil.