(CNN) -- Inspectors overseeing the destruction of Syria's chemical weapons have visited 21 of the 23 sites they want to inspect by a Friday deadline, but security concerns have prevented visits to the remaining two, the world's chemical weapons watchdog said Monday. "Efforts ... to ensure the conditions necessary for safe access to those sites will continue," the Organisation for the Prohibition of Chemical Weapons said in a statement released Monday. OPCW spokesman Michael Luhan added that the two remaining sites are in areas contested by government forces and opposition militants -- part of a conflict that has raged in the country since 2011.
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Inspectors were given until Friday to visit 23 chemical weapons sites
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Team has yet to reach two sites because of security concerns, OPCW says
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Team's task to oversee destruction of Syria's chemical weapons comes amid civil war
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U.N. giving Syria until mid-2014 to destroy its chemical weapons arsenal
According to the @placeholder, more than 100,000 people have died in the Syrian conflict.