David Chorney (L) stretches before a training run for the Boston Marathon in Boston, Massachusetts, April 3, 2014. Last year, officials stopped the race after two pressure cooker bombs exploded near ... more 
David Chorney (L) stretches before a training run for the Boston Marathon in Boston, Massachusetts, April 3, 2014. Last year, officials stopped the race after two pressure cooker bombs exploded near the finish line, killing three people and injuring more than 260. Along with tens of thousands of runners and hundreds of thousands of spectators, this year's event will feature an enhanced police presence. Some 3,500 law enforcement officers, double the number in 2013, will be posted along the 26.2 mile route and new restrictions will prohibit runners or spectators from carrying backpacks or other large parcels. Picture taken April 3, 2014. REUTERS/Brian Snyder (UNITED STATES - Tags: SPORT ATHLETICS ANNIVERSARY) less 
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Reuters | Photo By BRIAN SNYDER / BRIAN SNYDER
Mon, Apr 14, 2014 7:10 AM EDT