After a four day stand-off with al-Qaeda linked militants, Algerian special forces have stormed the desert gas facility where several people were still being kept hostage.
The state news agency says 11 militants were killed by the army at the In Amenas plant. Seven hostages also lost their lives as troops tried to free them.
The state oil and gas company Sonatrach says the militants had boob-trapped the complex with explosives.
Scores of westerners were inside the gas facility on Wednesday when it was seized by Islamist fighters.
During the crisis, hundreds of people were held captive and although most were released, dozens are thought to have died as Algerian troops fought on several occasions to take back the plant.
A further sixteen hostages were freed on Saturday, including two Americans. But the army also found 15 burned bodies at the plant.
The exact death toll including gunmen, Algerians and foreigners taken hostage is still unclear.