"The best way for us to react is to push ahead with the marathon, to get people on the streets and to celebrate it as we always do in London -- and to send a very clear message that we won't be cowed by this sort of behavior, " Sport Minister Hugh Robertson had earlier told the BBC.

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StubHub has the unique ability to analyze ticket purchasing behavior for sporting events by sport and by state.

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Sport (with a capital S) has unwritten (and written) rules about sportsmanlike behavior.

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