Article Photos: Boston Marathon reaction: No immediate changes planned in Oklahoma City Memorial Marathon 40/44

Medical workers aid an injured man at the 2013 Boston Marathon following an explosion in Boston, Monday, April 15, 2013. Two bombs exploded near the finish of the Boston Marathon on Monday, killing at least two people, injuring at least 22 others and sending authorities rushing to aid wounded spectators. (AP Photo/The Boston Globe, David L. Ryan) MANDATORY CREDIT ORG XMIT: MABOD901