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The Indianapolis 500 is an attractive target for terrorists, US government authorities said, but there has been no credible or specific threat aimed at the the United States' most famous motor race.
Officials said such sporting events, which attract hundreds of thousands of spectators, are attractive potential targets. The assessment said these popular events are inviting to terrorists because of the potential to inflict large numbers of casualties while the whole world is watching.
Officials estimate between 200,000 and 300,000 people will attend the Indy 500 next week.
