Armed assailants kidnapped five French nationals and two Africans working in Niger for French nuclear reactor builder Areva, diplomatic and company officials said on Thursday.

French Foreign Ministry spokesman Bernard Valero said the seven were kidnapped overnight near the mining town of Arlit, in Niger’s northern desert region.

In an electronic briefing, Mr. Valero said French authorities are “totally mobilized” to respond to the situation.

The seven, who included one person from Togo and another from Madagascar, were seized by armed men while they were sleeping, a diplomatic official said on condition of anonymity. He was not allowed to speak to the press on the matter.

In a joint statement, Areva and Vinci, the parent company of its subcontractor Satom, said one Areva employee and his wife were among those abducted. The others were Satom staffers, the statement said.

The companies “immediately stepped up their security measures for their employees in the area,” the statement said.

Areva spokeswoman Pauline Briand said the company had not yet received any claim of responsibility.

A Vinci spokeswoman said the five Satom employees had been working on an earth—moving project under Areva’s supervision.

Arlit, located in the Sahara region, about 745 miles (1,200 kilometers) northeast of the capital, Niamey, was built to house workers in two large uranium mines nearby.

Uranium, a metal used to make nuclear fuel, is a lucrative export for Niger, a desperately poor country. Areva, the world’s largest nuclear manufacturer, gets much of its uranium from Niger.

Areva employees working in Niger have been abducted in the past. In 2008, the company announced the release of four of its employees {hbox}” all French nationals, who had been kidnapped by a rebel group, the Movement for Justice, which opposes the mining of ancestral lands.

Al—Qaeda’s North African affiliate is also active in the region and has targeted French and other European nationals in previous kidnappings.

Al—Qaeda in the Islamic Maghreb, or North Africa, claimed responsibility for the July execution of an ailing 78—year—old French aid worker. Michel Germaneau was slain in Mali three months after his abduction in Niger in April.

The leader of al—Qaeda’s North African branch said the Frenchman was killed in retaliation for the deaths of six al—Qaeda members in a military operation in the Sahara.

Al—Qaeda in the Islamic Maghreb grew out of an Islamist insurgency movement in Algeria, formally merging with al—Qaeda in 2006 and spreading through the Sahel region.

The borders between the Sahel nations are porous, and militants move between the countries. Increasing concerns about terrorism and trafficking in northwest Africa prompted four countries in the region, Algeria, Mauritania, Mali and Niger, to open a joint military headquarters deep in the desert last April.

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