FILE - In this Wednesday, April 17, 2013 photo, FBI investigators check for evidence under portable toilets on Clarendon Street in Boston. (AP Photo/The Boston Globe, Bill Greene) MANDATORY CREDIT: ... more 
FILE - In this Wednesday, April 17, 2013 photo, FBI investigators check for evidence under portable toilets on Clarendon Street in Boston. (AP Photo/The Boston Globe, Bill Greene) MANDATORY CREDIT: THE BOSTON GLOBE, BILL GREENE less 
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Associated Press | Photo By The Boston Globe, Bill Greene
Sun, Apr 21, 2013 10:53 AM EDT