Algeria is expected to raise the death toll from the hostage crisis at a natural gas complex, as preliminary reports showed that at least 80 people were killed.

Algerian Prime Minister Abdelmalek Sellal was expected to announce updated casualty figures at a news conference on Monday.

The Algerian government has said at least 32 militants and 23 foreign and Algerian hostages were killed in the four-day Islamist siege of the facility that ended Saturday with a final government assault.

On Sunday, special forces searching the complex at In Amenas in eastern Algeria found 25 more bodies, but the corpses were so disfigured that it was hard to tell whether they were hostages or militants.

Philippine officials said Monday that six of those killed at the complex were Filipinos, while four other Filipinos were missing. The dead also include three British workers, one American, one French citizen and one Romanian.

About 20 other foreigners were unaccounted for, among them 10 Japanese workers.

Islamist militant leader Mokhtar Belmokhtar claimed responsibility for the attack in the name of al-Qaida. In an Internet statement released Sunday, he said 40 militants from Muslim and Western nations carried out the raid. Algerian security forces killed most of the hostage takers in Saturday's assault and later identified the bodies of two militants as Canadians.

Algerian authorities detained five surviving militants during a search of the area on Sunday. Security forces also were trying to clear away land mines placed around the complex by the kidnappers.

Belmokhtar said the raid was in response to French military operations against other al-Qaida-linked militants in neighboring Mali.

British Prime Minister David Cameron said Sunday that responsibility for the killings “lies squarely” with what he called the “terrorists who launched this vicious and cowardly attack.” French President Francois Hollande welcomed what he described as Algeria's “most appropriate” response to “coldly determined terrorists.”

Algerian troops carried out an initial rescue mission at the complex on Thursday, helping almost 700 Algerian workers and more than 100 foreigners to escape.

The foreign hostages included Americans, Austrians, Belgians, Britons, Colombians, French, Japanese, Malaysians, Norwegians and Romanians. The complex is jointly run by Algerian, British and Norwegian firms.