Tourists in masks use mobile phone cameras to snap shots of themselves during a heavily polluted day on Tiananmen Square in Beijing, China, Thursday, Jan. 16, 2014. Beijing's skyscrapers receded into ... more 
Tourists in masks use mobile phone cameras to snap shots of themselves during a heavily polluted day on Tiananmen Square in Beijing, China, Thursday, Jan. 16, 2014. Beijing's skyscrapers receded into a dense gray smog Thursday as the capital saw the season's first wave of extremely dangerous pollution, with the concentration of toxic small particles registering more than two dozen times the level considered safe. (AP Photo/Alexander F. Yuan) less 
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Associated Press | Photo By Alexander F. Yuan
Thu, Jan 16, 2014 1:08 AM EST