American hostages held by militants in Algeria
In the last several years, however, al-Qaida's influence in the poorly patrolled desert wastes of southern Algeria and northern Mali and Niger has grown and it operates smuggling and kidnapping networks throughout the area. Militant groups that seized control of northern Mali already hold seven French hostages as well as four Algerian diplomats.
The natural gas field where the attack occurred, however, is more than 1,000 kilometers (600 miles) from the Mali border, though it is just 60 miles (100 kilometers) from Libya's deserts.
BP, together with Norwegian company Statoil and the Algerian state oil company, Sonatrach, operate the gas field. A Japanese company, JGC Corp, provides services for the facility as well.
Prime Minister David Cameron's office said "several British nationals" are involved in the "ongoing incident," without giving an exact number.
Japanese Chief Cabinet Secretary Yoshihide Suga said the kidnapped foreigners possibly include Japanese employees of JGC.
"We are certain that JGC is the one affected," Suga said, adding that the government is now negotiating with local officials through diplomatic channels, asking to protect the lives of the Japanese nationals.
Japanese news agencies, citing unnamed government officials have said there are three Japanese hostages.
Statoil spokesman Lars Christian Bacher said the company had 13 Norwegian employees and a Canadian on the site and two of them have suffered minor injuries, but he would not comment about the situation of the others.
The Norwegian Newspaper Bergens Tidende, however, said a 55-year-old Norwegian working on the site called his wife to say he had been abducted.
Algeria had long warned against military intervention against the rebels in northern Mali, fearing the violence could spill over its own long and porous border. Though its position softened slightly after Hollande visited Algiers in December, Algerian authorities remain skeptical about the operation and worried about its consequences on the region.
Algeria is Africa's biggest country, and has been an ally of the U.S. and France in fighting terrorism for years. But its relationship with France has been fraught with lingering resentment over colonialism and the bloody war for independence that left Algeria a free country 50 years ago.
Algeria's strong security forces have struggled for years against Islamist extremists, and have in recent years managed to nearly snuff out violence by al-Qaida in the Islamic Maghreb around its home base in northern Algeria. In the meantime, AQIM moved its focus southward.
AQIM has made tens of millions of dollars off kidnapping in the region, abducting Algerian businessmen or political figures, and sometimes foreigners, for ransom.
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