Breaking News of the Day: Boston Marathon Explosions

At least two explosions rocked the finish line at the Boston Marathon earlier this afternoon, killing at least two people and injuring at least a half-dozen of others (as of 4:21 pm ET). Within minutes of the explosions, disturbing pictures from the scene began circulating on Twitter and Facebook, including a Vine video showing one of the explosions as it happened. Our thoughts and prayers go out to the victims and others affected by this event. Stay tuned for more updates.