The brothers suspected of the Boston Marathon bombings originally planned to carry out the attack on July 4 this year, a law enforcement official has said.
But the official claimed the Tsarnaev brothers decided to strike earlier because they completed building their bombs more quickly than expected.
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There are reports that at least some MPs and Lords have been left unable to access their emails as a result of the attack.
Cuillin, six, and four-year-old Lejla designed the memorial plaque to their mum that has been installed in the Commons chamber.
Over-abstraction and an exceptionally dry winter are affecting hundreds of streams in England and Wales, warn wildlife experts.