In the northern Syrian city of Aleppo last month, there was a class about how to protect against chemical weapons attacks. J.M. Lopez/AFP/Getty Images hide caption

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A photo released by the Syrian official news agency SANA Thursday shows an international expert working at a chemical weapons plant in Syria. Destroying the weapons safely may require them to be moved to another country, experts say. AP hide caption

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U.N. chemical weapons experts carry samples collected on Aug. 28 from a site of an alleged chemical weapons attack near the Syrian capital Damascus. The Organization for the Prohibition of Chemical Weapons, which is dismantling Syria's chemical weapons stockpile, was awarded the 2013 Nobel Peace Prize on Friday. Reuters /Landov hide caption

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A United Nations vehicle carrying inspectors from the Organization for the Prohibition of Chemical Weapons (OPCW) leaves a hotel in Damascus, on Wednesday. Some 19 OPCW arms experts are in Syria and have started to destroy weapons production facilities. Louai Behara/AFP/Getty Images hide caption

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A convoy of chemical weapons disarmament experts depart the Four Seasons Hotel in Damascus, Syria, on Tuesday. A second team of experts will soon join mission to destroy Syria's chemical program. AP hide caption

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United Nations vehicles leave a Damascus hotel last week. The team of international disarmament experts began to dismantle Syria's chemical weapons production facilities on Sunday. Louai Beshara/AFP/Getty Images hide caption

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A convoy of U.N. vehicles with chemical weapons experts on board head out on Friday to do more work as the investigate allegations of chemical weapons use in near Damascus. Louai Beshara /AFP/Getty Images hide caption

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A rebel fighter cleans his weapon in the northern Syrian city of Aleppo Friday. Syria's civil war continues, even as the country follows a schedule of releasing information on its chemical weapons program. AFP/AFP/Getty Images hide caption

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