The Amenas gas field in Algeria is seen in this September 10, 2012 handout satellite image courtesy of Google Earth. REUTERS/Google Earth/GeoEye/Handout (ALGERIA - Tags: CIVIL UNREST ENERGY) FOR EDITORIAL USE ONLY. NOT FOR SALE FOR MARKETING OR ADVERTISING CAMPAIGNS. NO ARCHIVES. NO SALES. THIS IMAGE HAS BEEN SUPPLIED BY A THIRD PARTY. IT WAS PROCESSED BY REUTERS TO ENHANCE QUALITY. AN UNPROCESSED VERSION WAS PROVIDED SEPARATELY The Amenas gas field in Algeria is seen in this September 10, 2012 handout satellite image courtesy of Google Earth. REUTERS/Google Earth/GeoEye/Handout (ALGERIA - Tags: CIVIL UNREST ENERGY) FOR EDITORIAL USE ONLY. NOT FOR SALE FOR MARKETING OR ADVERTISING CAMPAIGNS. NO ARCHIVES. NO SALES. THIS IMAGE HAS BEEN SUPPLIED BY A THIRD PARTY. IT WAS PROCESSED BY REUTERS TO ENHANCE QUALITY. AN UNPROCESSED VERSION WAS PROVIDED SEPARATELY This Oct. 8, 2012 satellite image provided by DigitalGlobe shows the Amenas Gas Field in Algeria, which is jointly operated by BP and Norway's Statoil and Algeria's Sonatrach. Algerian special forces launched a rescue operation Thursday at the plant in the Sahara Desert and freed foreign hostages held by al-Qaida-linked militants, but estimates for the number of dead varied wildly from four to dozens. (AP Photo/DigitalGlobe) This Oct. 8, 2012 satellite image provided by DigitalGlobe shows the Amenas Gas Field in Algeria, which is jointly operated by BP and Norway's Statoil and Algeria's Sonatrach. Algerian special forces launched a rescue operation Thursday at the plant in the Sahara Desert and freed foreign hostages held by al-Qaida-linked militants, but estimates for the number of dead varied wildly from four to dozens. (AP Photo/DigitalGlobe) Hostages react after they were freed from a gas facility in Algeria where Islamist militants were holding them in Tigantourine, in this still image taken from video footage January 18, 2013. About 60 foreigners were still being held hostage or missing inside a gas plant on Friday after Algerian forces stormed the desert complex to free hundreds of captives taken by Islamist militants, who threatened to attack other energy installations. REUTERS/Algerian TV via Reuters TV less An unidentified rescued hostage speaks to the media in a hospital in Ain Amenas, Algeria, in this image taken from television Friday Jan. 18, 2013. Algeria's state news service says nearly 100 out of 132 foreign hostages have been freed from a gas plant where Islamist militants had held them captive for three days. The APS news agency report was an unexpected indication of both more hostages than had previously been reported and a potentially breakthrough development in what has been a bloody siege. (AP Photo/Canal Algerie via Associated Press TV) less An unidentified rescued hostage speaks to the media in a hospital Ain Amenas, Algeria, in this image taken from television Friday Jan. 18, 2013. Algeri'ís state news service says nearly 100 out of 132 foreign hostages have been freed from a gas plant where Islamist militants had held them captive for three days. The APS news agency report was an unexpected indication of both more hostages than had previously been reported and a potentially breakthrough development in what has been a bloody siege. (AP Photo/Canal Algerie via Assiaciated Press TV) less An unidentified rescued hostage receives treatment in a hospital in Ain Amenas, Algeria, in this image taken from television Friday Jan. 18, 2013. Algeria's state news service says nearly 100 out of 132 foreign hostages have been freed from a gas plant where Islamist militants had held them captive for three days. The APS news agency report was an unexpected indication of both more hostages than had previously been reported and a potentially breakthrough development in what has been a bloody siege. (AP Photo/Canal Algerie via Associated Press TV) less A wounded hostage is seen on a hospital bed after they were freed from a gas facility in Algeria where Islamist militants were holding them in Tigantourine, in this still image taken from video footage January 18, 2013. About 60 foreigners were still being held hostage or missing inside a gas plant on Friday after Algerian forces stormed the desert complex to free hundreds of captives taken by Islamist militants, who threatened to attack other energy installations. REUTERS/Algerian TV via Reuters TV ( less Unidentified rescued hostages pose for the media in Ain Amenas, Algeria, in this image taken from television Friday Jan. 18, 2013. Algeria's state news service says nearly 100 out of 132 foreign hostages have been freed from a gas plant where Islamist militants had held them captive for three days. The APS news agency report was an unexpected indication of both more hostages than had previously been reported and a potentially breakthrough development in what has been a bloody siege. (AP Photo/Canal Algerie via Associated Press TV) less A freed hostage speaks after they were freed from a gas facility in Algeria where Islamist militants were holding them in Tigantourine, in this still image taken from video footage January 18, 2013. About 60 foreigners were still being held hostage or missing inside a gas plant on Friday after Algerian forces stormed the desert complex to free hundreds of captives taken by Islamist militants, who threatened to attack other energy installations. REUTERS/Algerian TV via Reuters TV less An ambulance believed to be carrying a wounded hostage from a gas facility where Islamist militants were holding them arrives at a hospital in In Amenas January 18, 2013. Algerian forces have freed about 100 of the 132 foreigners who were taken hostage in a gas facility in the Algerian desert, a security source told Reuters. REUTERS/Ramzi Boudina (ALGERIA - Tags: CIVIL UNREST POLITICS ENERGY) An ambulance believed to be carrying a wounded hostage from a gas facility where Islamist militants were holding them arrives at a hospital in In Amenas January 18, 2013. Algerian forces have freed about 100 of the 132 foreigners who were taken hostage in a gas facility in the Algerian desert, a security source told Reuters. REUTERS/Ramzi Boudina (ALGERIA - Tags: CIVIL UNREST POLITICS ENERGY) Oil workers from India, Pakistan and Philippines wait before boarding their flight after arriving to Palma de Mallorca airport at Spanish Balearic island of Mallorca, January 18, 2013. Oil workers evacuated from Algeria following an Al Qaeda linked attack arrived at Palma de Mallorca airport on Thursday night and wait for connecting flights home. REUTERS/Enrique Calvo (SPAIN - Tags: CIVIL UNREST) Oil workers from India, Pakistan and Philippines wait before boarding their flight after arriving to Palma de Mallorca airport at Spanish Balearic island of Mallorca, January 18, 2013. Oil workers evacuated from Algeria following an Al Qaeda linked attack arrived at Palma de Mallorca airport on Thursday night and wait for connecting flights home. REUTERS/Enrique Calvo (SPAIN - Tags: CIVIL UNREST)