Updated 9:35 p.m. ALGIERS, Algeria The death toll from the terrorist siege at a natural gas plant in the Sahara climbed past 80 on Sunday as Algerian forces searching the refinery for explosives found dozens more bodies, many so badly disfigured it was unclear whether they were hostages or militants, a security official said. Algerian special forces stormed the plant on Saturday to end the four-day siege, moving in to thwart what government officials said was a plot by the Islamic extremists to blow up the complex and kill all their captives with mines sown throughout the site. Agence France Presse reports local officials are claiming that five kidnappers were found alive on site after the raid. In a statement, the Masked Brigade, the group that claimed to have masterminded the takeover, warned of more such attacks against any country backing France's military intervention in neighboring Mali, where the French are trying to stop an advance by Islamic extremists. "We stress to our Muslim brothers the necessity to stay away from all the Western companies and complexes for their own safety, and especially the French ones," the statement said. Algeria said after Saturday's assault by government forces that at least 32 extremists and 23 hostages were killed. On Sunday, Algerian bomb squads sent in to blow up or defuse the explosives found 25 more bodies, said the security official, who spoke on condition of anonymity because of the sensitivity of the situation. The dead hostages were also known to include at least one American as well as Filipino and French workers. Nearly two dozen foreigners by some estimates were unaccounted for. Two private Algerian TV stations and an online news site said security forces scouring the plant found five militants hiding out and learned that three others had fled. That information could not be immediately confirmed by security officials. Authorities said the bloody takeover was carried out Wednesday by 32 men from six countries, under the command from afar of the one-eyed Algerian bandit Moktar Belmoktar, founder of the Masked Brigade, based in Mali. The Masked Brigade said Sunday the attack was payback against Algeria for allowing over-flights of French aircraft headed to Mali and for closing its long border with Mali. In an earlier communication, the Brigade claimed to have carried out the attack in the name of al Qaeda. The militants had "decided to succeed in the operation as planned, to blow up the gas complex and kill all the hostages," Algerian Communications Minister Mohamed Said told state radio. Norwegian Foreign Minister Espen Barth Eide said the terrorists had tried to blow up the plant on Saturday but managed only to start a small fire. "That's when they started to execute hostages, and the special forces intervened," Eide said. Norway's Statoil said five Norwegians were still missing. An organization that monitors videos from radicals posted one showing al-Nigiri with what appeared to be an explosive belt around his waist. David Plouffe, a senior adviser to President Barack Obama, said that al Qaeda and al Qaeda-affiliated groups remain a threat in North Africa and other parts of the world, and that the U.S. is determined to help other countries destroy those networks.