The church bells rang out in Boston following a moment of silence honouring those affected by the marathon bombings a year ago today.
As an American flag was raised the crowd, including Vice President Joe Biden, sang the National Anthem.
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Scientists concluded 12.5% of cardiovascular deaths could be avoided if more Britons changed their diets.
Chelsea Clinton has brushed off Donald Trump's threat to bring up her father's infidelities in a recent interview.
Sir Tom will be joined on the panel by Oscar-winning actress and singer Jennifer Hudson and rock star Gavin Rossdale.