FILE - In this Monday, April 15, 2013 file photo, people react as an explosion goes off near the finish line of the 2013 Boston Marathon in Boston. Event after nail-biting event, America was rocked ... more 
FILE - In this Monday, April 15, 2013 file photo, people react as an explosion goes off near the finish line of the 2013 Boston Marathon in Boston. Event after nail-biting event, America was rocked this week, in rare and frightening ways, with what felt like an unremitting series of tragedies. (AP Photo/The Boston Globe, David L Ryan, File) MANDATORY CREDIT: THE BOSTON GLOBE, DAVID L RYAN less 
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Associated Press | Photo By The Boston Globe, David L Ryan, File
Sat, Apr 20, 2013 9:52 AM EDT