The office workers cover their mouths and noses while others wear masks as they cross a road on Thursday, June 20, 2013. Singapore urged people to remain indoors amid unprecedented levels of air ... more 
The office workers cover their mouths and noses while others wear masks as they cross a road on Thursday, June 20, 2013. Singapore urged people to remain indoors amid unprecedented levels of air pollution Thursday as a smoky haze wrought by forest fires in neighboring Indonesia worsened dramatically. (AP Photo/Joseph Nair) less 
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Associated Press | Photo By Joseph Nair
Thu, Jun 20, 2013 12:18 PM EDT