A runner is escorted from the scene after explosions went off at the 117th Boston Marathon in Boston, Massachusetts April 15, 2013. Two explosions hit the Boston Marathon as runners crossed the finish line on Monday, killing at least two people and injuring 23 on a day when tens of thousands of people pack the streets to watch one of the world’s best known marathons. REUTERS/Jessica Rinaldi (UNITED STATES — Tags: CIVIL UNREST DISASTER SPORT ATHLETICS) — RTXYMXE