Police officers man a barricade in the vicinity of finish line of Monday's Boston Marathon explosions, which killed at least three and injured more than 140, Wednesday, April 17, 2013, in Boston. (AP ... more 
Police officers man a barricade in the vicinity of finish line of Monday's Boston Marathon explosions, which killed at least three and injured more than 140, Wednesday, April 17, 2013, in Boston. (AP Photo/Matt Rourke) less 
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Associated Press | Photo By Matt Rourke
Thu, Apr 18, 2013 6:12 AM EDT