Updated Thursday, January 17, 2013 at 06:36 AM
ALGIERS, Algeria — In a desert standoff deep in the Sahara, the Algerian army ringed a natural-gas complex where Islamist militants hunkered down with dozens of hostages late Wednesday after a rare attack that appeared to be the first violent shock wave from the French intervention in Mali.
A militant group that claimed responsibility said 41 foreigners, including seven Americans, were being held after the assault on one of oil-rich Algeria’s energy facilities, 800 miles from the capital, Algiers, and 1,000 miles from the coast. Two foreigners were killed.
The group claiming responsibility said the attack was in revenge for Algeria’s support of France’s military operation against al-Qaida-linked rebels in neighboring Mali.
The militants appeared to have no escape, with troops surrounding the complex and army helicopters clattering overhead.
The group — Katibat Moulathamine, or the Masked Brigade — phoned a Mauritanian news outlet to say one of its affiliates had carried out the operation at the Ain Amenas gas field, and France should end its intervention in Mali to ensure the safety of the hostages.
BP, the Norwegian company Statoil and the Algerian state oil company Sonatrach, operate the gas field. A Japanese company, JGC, also provides services for the facility.
In Rome, Defense Secretary Leon Panetta said the U.S. “will take all necessary and proper steps” to deal with the attack in Algeria. He likened it to al-Qaida activities in Pakistan, Afghanistan and in the United States on Sept. 11, 2001.
Algeria’s top security official, Interior Minister Daho Ould Kabila, said troops had cornered the terrorists, and that one Briton and one Algerian were killed in the attack, while a Norwegian and two other Britons were among the six wounded.
There were reports of clashes between the two sides and a member of the militant group told the Mauritanian news outlet the Islamists had repelled one assault by Algerian soldiers late Wednesday.
Ireland said the hostages included a 36-year-old married Irish man. Japan, Britain and the U.S. said their citizens were taken. A Norwegian woman said her husband called her saying that he had been taken hostage.
Hundreds of Algerians work at the plant and also were captured in the attack, but the Algerian state news agency reported they were gradually released unharmed Wednesday.
Kabila, the Algerian minister, said it seemed the militants were hoping to negotiate their departure from the area, a notion he rejected. He also dismissed theories that the militants had come from Libya, 60 miles away, or from Mali, more than 600 miles away.
Kabila said the roughly 20 well-armed gunmen were from Algeria, operating under orders from Moktar Belmoktar, al-Qaida’s strongman in the Sahara.
A caller to the Nouakchott Information Agency, which often carries announcements from extremist groups, said the kidnapping was carried out by “Those Who Signed in Blood,” a group created to attack countries participating in the offensive against Islamist groups in Mali.
The Masked Brigade was formed by Belmoktar, a one-eyed Algerian who recently said he was leaving the terrorist network’s Algerian branch, al-Qaida in the Islamic Maghreb, to create his own group.
A close associate of Belmoktar blamed the West for France’s recent air and ground intervention against Islamist fighters in Mali.
“It’s the United Nations that gave the green light to this intervention and all Western countries are now going to pay a price. We are now globalizing our conflict,” Oumar Ould Hamaha said in a telephone interview late Wednesday.
French President François Hollande launched the operation in Mali, a former French colony in West Africa, on Friday, hoping to stop the al-Qaida-linked and other Islamist extremists whom he believes pose a danger to the world.
Attacks on oil-rich Algeria’s hydrocarbon facilities are rare, despite decades of fighting an Islamist insurgency, mostly in northern Algeria.
Algeria, Africa’s biggest country, 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.