According to a law enforcement source, suspected bomber, Dzhokhar Tsarnaev claimed responsibility for the attacks in a scribbled message that was found in the boat where he was hiding.
In the message, the source says Tsarnaev calls the bombing victims collateral damage in a strike meant as payback for U.S. wars in muslim lands.
CNN's Susan Candiotti is in Boston with more on the investigation.
While everyone else was busy blaming right-wing groups for the bombing, I felt like the only one asking, "What if this is more blowback?" You can't have a foreign policy that annihilates women and children with drone bombs and not expect someone to be outraged enough to want to take revenge. It's like we learned nothing from the fallout of 9/11.