ABC News is reporting that Dzhokhar Tsarnaev informed the FBI that he and his brother, Tamerlan, originally scheduled their attack for Jul. 4. Their decision to strike on Apr. 15 was motivated by their shock at "how quickly they were able to build functioning explosives." The report also claims that Tsarnaev told agents the pressure cooker bombs were constructed in his brother's Cambridge, MA apartment. 

However, a law enforcement source close the New York Times offers a different account. According to them, the brothers planned a suicide attack. Tsarnaev reportedly told the FBI that he and his brother "considered suicide attacks and striking on the Fourth of July as they plotted their deadly assault" before opting for pressure cooker bombs and other explosives they assembled on their own.

A source also told the Times that female DNA was discovered on the bombs, and although authorities are curious about the possible role that Tamerlan Tsarnaev's wife, Katherine Russell, might have had in their plot, they've allegedly acknowledged that the DNA does not belong to her.

[via Gothamist, ABC News and the New York Times]

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