In this image from video provided by WBZ TV, spectators and runners run from what was described as twin explosions that shook the finish line of the Boston Marathon, Monday, April 15, 2013, in Boston. Two explosions shattered the euphoria of the Boston Marathon finish line on Monday, sending authorities out on the course to carry off the injured while the stragglers were rerouted away from the smoking site of the blasts. (AP Photo/WBZTV) MANDATORY CREDIT
Wesley Korir (left) and Sharon Cherop, both of Kenya, kiss the winner's trophy after winning the men's and women's divisions of the 116th Boston Marathon in Boston on April 16, 2012. (Associated Press)
ASSOCIATED PRESS PHOTOGRAPHS
Geoffrey Mutai of Kenya takes the final strides of the fastest marathon ever run in the men's division of the 115th Boston Marathon. Strong winds helped Mutai post a time of 2:03.02.
Robert Kiprono Cheruiyot of Kenya, winner of men's elite division of the 2010 Boston Marathon, listens to reporter's question during a news conference for the 115th Boston Marathon, Friday, April 15, 2011, in Boston. The Boston Marathon is schedulted to run on Monday, April 18. (AP Photo/Bizuayehu Tesfaye)