The attackers then invaded the complex itself. Only three of the attackers were Algerian, the ministry said. The others were of “different nationalities.” Some of the attackers were explosives experts, the ministry said.

The Algerian government defended the aggressive way in which it responded to the attack, saying it feared the attackers intended to blow up the natural gas facility and then escape into the desert with their hostages.

It described all 32 of the attackers as “neutralized,” suggesting that none had been captured alive, and said a wide varietey of weapons had been recovered, including two mortars, two rocket-propelled grenade launchers, six miliary machine guns, 21 assault rifles and a variety of explosives.

Considered home of North Africa’s best military, Algeria also remains a nation scared by a brutal decade-long civil war between government and Islamists for control of the country. The war, which ended in 2002, left 200,000 dead, 100,000 displaced and a nation whose government is fearful and intolerant of extremism within its borders.

Survivors of the events told harrowing tales of both the initial assault and their escape. Attackers came from all sides at both the residential compound and the gas plant site and quickly separated the Algerians from the foreigners. Those who escaped Thursday and Friday said they could only do so when a surprise Algerian military offensive killed the kidnappers, in one case by striking a Jeep from the air and killing the militants inside.

Algeria has identified the kidnappers as members of an al Qaida-affiliated group led by Mokhtar Belmokhtar, a longtime militant who is described as charismatic, ruthless and stubborn. In a statement Wednesday, hours after the kidnappers snatched the gas line workers, Belmokhtar’s group said the attack was in retaliation for the French-led offensive in Mali.

It was not clear if Belmokhtar had been among the kidnappers.