Thirty-two terrorists and 23 captives were killed in the remote In Amenas gas facility in the Sahara desert, the Algerian Interior Ministry said Saturday, after the military launched a bloody final assault to end a four-day hostage standoff.
The nationalities of the hostages were not released and the government said this was a provisional toll.
"This intervention resulted in the release of 685 Algerian employees and 107 foreigners," the ministry said, according to the APS state news agency.
The military recovered machine guns, rifles, shotguns, mortars, missiles, missile launchers, rockets, grenades and foreign military uniforms from the site, APS reported.
Seven hostages were executed, the El Watan newspaper reported, by the Islamist insurgents before the military stormed the facility.
The military operation that started Thursday to free a group of foreign and Algerian workers had been criticized by some countries whose citizens were being held.
But on Saturday, French President Francois Hollande acknowledged that Algeria had no choice but to storm the complex. He said that while all the details were not yet known, when there's a hostage situation with cold-blooded terrorists who were ready to kill, then "a country like Algeria responds in a way which, to my eyes, is the most suitable."
Negotiations with the hostage-takers was not possible, Hollande said, adding that he found Algeria's handling of the situation as "the most appropriate" response.
British Prime Minister David Cameron, who spoke with his Algerian counterpart Abdelmalek Sellal, said: "There is no justification for taking innocent life in this way." "Our determination is stronger than ever to work with allies right around the world to root out and defeat this terrorist scourge and those who encourage it."
At a news conference with US Defense Secretary Leon Panetta, British Defense Secretary Philip Hammond said: "The loss of life as a result of these attacks is appalling and unacceptable. We must be clear that it is the terrorists who bear sole responsibility for it."
British Foreign Secretary William Hague said that five British nationals and one resident were dead or unaccounted for.
The attack on the In Amenas gas field, one of Algeria's biggest and operated by Britain's BP, Norway's Statoil and Algerian state company Sonatrach, came after militants affiliated to al-Qaeda took hundreds of workers hostage early Wednesday.
BP chief executive Bob Dudley said the company was "unable to confirm the location or situation" of four employees and had "grave fears" for their fate.
In Tokyo, Japanese Prime Minister Shinzo Abe said early Sunday: "The Algerian government provided us with somber information about the safety of Japanese nationals," the Kyodo news agency reported after Abe spoke over the phone with the Algerian premier.
Norwegian Prime Minister Jens Stoltenberg said in Oslo after the operation had ended that they would have to face the fact that Norwegian nationals were likely killed.
Foreign Minister Espen Barth Eide said Norway supported the final military raid by Algeria. "In this situation it was necessary to quickly intervene and rescue as many hostages as possible." Norway was earlier critical of Algeria's decision to go it alone and not provide advance warning of its operation.
An Algerian government source told APS that the mission was carried out in "extremely complex circumstances" against heavily armed terrorists.
Sonatrach said Saturday the army had started a massive operation to clear mines planted by the militants around the complex. "After the army stormed the gas complex and evicted the terrorists, it was noticed that mines had been placed to blow up the factory," the company said.
State television showed footage of some freed hostages. "Hadn't it been for the army intervention, we would have been a matter of the past," an Algerian hostage, who was not named, said.
He added that the raid had surprised the kidnappers and given some hostages the chance to escape.
Algeria, which is still recovering from a brutal Islamist insurgency in the 1990s, declared from the outset it would not negotiate with the militants.
The In Amenas saga has been linked to the escalation in the conflict in neighbouring Mali, where France last week launched a military operation against Islamist militants controlling much of the north.
On Friday, Panetta said: "Terrorists should be on notice that they will find no sanctuary, no refuge, not in Algeria, not in North Africa, not anywhere. Those who would wantonly attack our country and our people will have no place to hide."
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