ALGIERS - Algerian special forces stormed a natural gas complex in the Sahara desert on Saturday to end a standoff with Islamist extremists that left at least 19 hostages and 29 militants dead.
Dozens of foreign workers remain unaccounted for, leading to fears the death toll could rise.
With few details emerging from the remote site in eastern Algeria, it was unclear whether anyone was rescued in the final operation.
The siege at Ain Amenas transfixed the world after radical Islamists linked to al-Qaida stormed the complex, which contained hundreds of plant workers from all over the world, and then held them hostage surrounded by the Algerian military and its attack helicopters for four tense days that were punctuated with gunbattles and dramatic tales of escape.
Algeria's response to the crisis was typical of the country's history in confronting terrorists, favoring military action over negotiation, which caused an international outcry from countries worried about their citizens. Algerian military forces twice assaulted the two areas where the hostages were being held with minimal apparent mediation - first on Thursday and then on Saturday.
In the final assault, the remaining band of militants killed seven hostages before special forces killed 11 of the attackers, the state news agency said. It wasn't immediately possible to verify who killed the hostages. The military launched its assault to prevent a fire started by the extremists from engulfing the complex, the report said.
The seven hostages and 11 militants adds to the previous toll of 12 captives and 18 kidnappers, according to the government, but there are fears that the number of hostages killed is much higher and dozens of foreign workers from the Ain Amenas site remain unaccounted for.
Sonatrach, the Algerian state oil company running the site along with BP and Norway's Statoil, said the entire refinery had been mined with explosives, and the process of clearing it out had begun, indicating the militants planned to blow up the complex - one of the largest in oil and gas-rich Algeria.