Students wear masks to protect against volcanic ash in the air during lessons at a school in the Berastagi village of Karo district, Indonesia's North Sumatra province September 20, 2013. Mount ... more 
Students wear masks to protect against volcanic ash in the air during lessons at a school in the Berastagi village of Karo district, Indonesia's North Sumatra province September 20, 2013. Mount Sinabung threw more volcanic ash into air, covering the surrounding areas, local media reported on Wednesday. REUTERS/YT Haryono (INDONESIA - Tags: DISASTER ENVIRONMENT EDUCATION) less 
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Reuters | Photo By STRINGER/INDONESIA / REUTERS
Fri, Sep 20, 2013 7:39 AM EDT