This undated photo provided by the U.S. Marines shows Lance Cpl. David P. Fenn II of Polk City, Fla. Penn, 20, was killed with six other Marines in an explosion during a Nevada training exercise on ... more 
This undated photo provided by the U.S. Marines shows Lance Cpl. David P. Fenn II of Polk City, Fla. Penn, 20, was killed with six other Marines in an explosion during a Nevada training exercise on Monday, March 18, 2013. (AP Photo/U.S. Marines) less 
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Associated Press | Photo By U.S. Marines
Thu, Mar 21, 2013 8:34 PM EDT