Looking for someone caught up in the explosions? Have information about someone caught in the explosions? Google have setup a people finder to help on both fronts:

http://google.org/personfinder/2013-boston-explosions

EDIT: From Sky News UK

Boston Police said there is a helpline in the US for concerned relatives: 617 635 4500, and anybody with information about the blasts should call 1 800 494 tips.

The UK consulate in Boston said British Nationals in need of emergency consular assistance should call the Global Response Centre on 1 877 854 6872.

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