Two dead, up to 100 injured, multiple devices, with ball bearing shrapenel, probably cell phone activated, planted near the finish line.
That's about all we know at this point. A horrible crime, but nobody to point the finger at yet.
Initial reports suggest a Saudi student was arrested at the scene and is in custody, but that he was wounded in the attack. CNNs National Security Analyst Peter Bergen said it reminded him of Oklahoma City or other right-wing groups. Remember, the media has an established track record for speculating that violent attacks are the work of the right-wing groups, and then being proved wrong.
I hope the authorities find the answer as quickly as possible, and bring the bombers to justice.