Alex Fusco, one of the first on scene after the bombing, was among the crowds at the memorial service
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Boston marks anniversary of marathon bombing

Boston is marking the anniversary of the deadly bombing at last year's marathon, honouring the dead and lauding the character and strength of the survivors and the city's residents.

US Vice-President Joe Biden told survivors they were an example of "pure courage".

Rajini Vaidyanathan reports.

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