Boston Marathon runner Vu Trang, of San Francisco, cries at a makeshift memorial on Boylston Street near the finish line of Monday's Boston Marathon explosions, which killed at least three and injured... more 
Boston Marathon runner Vu Trang, of San Francisco, cries at a makeshift memorial on Boylston Street near the finish line of Monday's Boston Marathon explosions, which killed at least three and injured more than 140, in Boston, Wednesday, April 17, 2013. The bombs that blew up seconds apart near the finish line left the streets spattered with blood and glass, and gaping questions of who chose to attack at the Boston Marathon and why. (AP Photo/Charles Krupa) less 
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Associated Press | Photo By Charles Krupa
Wed, Apr 17, 2013 4:09 PM EDT