ALGIERS, Algeria - Algerian helicopters and special forces stormed a gas plant in the stony plains of the Sahara on Thursday to wipe out Islamist militants and free hostages from at least 10 countries. Bloody chaos ensued, leaving the fate of the fighters and many of the captives uncertain.
Dueling claims from the military and the militants muddied the world's understanding of an event that angered Western leaders, raised world oil prices and complicated the international military operation in neighboring Mali.
At least six people, and perhaps many more, were killed - Britons, Filipinos and Algerians. Terrorized hostages from Ireland and Norway trickled out of the Ain Amenas plant, families urging them never to return.
This April 19, 2005, photo shows the Ain Amenas gas field in Algeria, where Islamist militants raided and took hostages Wednesday.
Dozens more remained unaccounted for: Americans, Britons, French, Norwegians, Romanians, Malaysians, Japanese, Algerians and the fighters themselves.
A U.S. official said late Thursday that while some Americans escaped, other Americans remain either held or unaccounted for. The official spoke on condition of anonymity.
The U.S. government sent an unmanned surveillance drone to the BP-operated site, near the border with Libya and 800 miles from the Algerian capital, but it could do little more than watch Thursday's intervention. Algeria's army-dominated government, hardened by decades of fighting Islamist militants, shrugged aside foreign offers of help - including from the U.S. - and drove ahead alone.
With the hostage drama entering its second day Thursday, Algerian security forces moved in, first with helicopter fire and then special forces, according to diplomats, a website close to the militants, and an Algerian security official. The government said it was forced to intervene because the militants were being stubborn and wanted to flee with the hostages.
The militants - led by a Mali-based al-Qaida offshoot known as the Masked Brigade - suffered losses in Thursday's military assault, but succeeded in garnering a global audience.
Even violence-scarred Algerians were stunned by the brazen hostage-taking Wednesday, the biggest in northern Africa in years and the first to include Americans as targets. Mass fighting in the 1990s had largely spared the lucrative oil and gas industry that gives Algeria its economic independence and regional weight.
The hostage-taking raised questions about security for sites run by multinationals that are dotted across Africa's largest country. It also raised the prospect of similar attacks on other countries allied against the extremist warlords and drug traffickers who rule a vast patch of desert across several countries in northwest Africa. Even the heavy-handed Algerian response may not deter groups looking for martyrdom and attention.
Casualty figures in the Algerian standoff varied widely. The remote location is extremely hard to reach and was surrounded by Algerian security forces - who, like the militants, are inclined to advertise their successes and minimize their failures.
"An important number of hostages were freed and an important number of terrorists were eliminated, and we regret the few dead and wounded," Algeria's communications minister, Mohand Said Oubelaid, told national media, adding that the "terrorists are multinational," coming from several different countries with the goal of "destabilizing Algeria, embroiling it in the Mali conflict and damaging its natural gas infrastructure."
The official news agency said four hostages were killed in Thursday's operation, two Britons and two Filipinos. Two others, a Briton and an Algerian, died Wednesday in an ambush on a bus ferrying foreign workers to an airport. Citing hospital officials, the APS news agency said six Algerians and seven foreigners were injured.
APS said some 600 local workers were safely freed in the raid - but many of those were reportedly released the day before by the militants themselves.
The militants, via a Mauritanian news website, claimed that 35 hostages and 15 militants died in the helicopter strafing. A spokesman for the Masked Brigade told the Nouakchott Information Agency in Mauritania that only seven hostages survived.
By nightfall, Algeria's government said the raid was over. But the whereabouts of the rest of the plant workers was unclear.
President Barack Obama and British Prime Minister David Cameron spoke on the phone to share their confusion. White House Press Secretary Jay Carney said the Obama administration was "seeking clarity from the government of Algeria."
Militants earlier said they were holding seven Americans, but the administration confirmed only that Americans were among those taken.
BP, the Norwegian company Statoil and the Algerian state oil company Sonatrach, operate the gas field and a Japanese company, JGC Corp, provides services for the facility.
Japan's Prime Minister Shinzo Abe protested the military raid as an act that "threatened the lives of the hostages."
Jean-Christophe Gray, a spokesman for Cameron, said Britain wasn't informed in advance of the raid.
One Irish hostage managed to escape: electrician Stephen McFaul, who'd worked in North Africa's oil and natural gas fields off and on for 15 years. His family said the militants let hostages call their families to press the kidnappers' demands.
"He phoned me at 9 o'clock to say al-Qaida were holding him, kidnapped, and to contact the Irish government, for they wanted publicity. Nightmare, so it was. Never want to do it again. He'll not be back! He'll take a job here in Belfast like the rest of us," said his mother, Marie.