The brothers suspected of the Boston Marathon bombings had originally planned to carry out the attack on July 4 this year, a law enforcement official said.

But the Tsarnaev brothers decided to strike earlier because they completed building their bombs more quickly than expected, the official said.

NewsdayTV goes behind the scenes of the day Rex Heuermann was sentenced for the Gilgo killings. Credit: Newsday Staff

'A million years isn't enough' NewsdayTV goes behind the scenes of the day Rex Heuermann was sentenced for the Gilgo killings.

NewsdayTV goes behind the scenes of the day Rex Heuermann was sentenced for the Gilgo killings. Credit: Newsday Staff

'A million years isn't enough' NewsdayTV goes behind the scenes of the day Rex Heuermann was sentenced for the Gilgo killings.

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