Six days later, the backpack they'd thrown away was found -- this time in a New Bedford landfil.

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In addition to the backpack ban, spectators at the events will be searched each time they enter the facility.

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They also throw a pre-Derby party around the race to help out a charity called Blessings in a Backpack, a program that feeds elementary school children on the weekend across 32 states and three countries.

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Inside the backpack, they found fireworks, a jar of Vaseline and UMass-Dartmouth homework materials for classes in which Mr. Tsarnaev was enrolled.

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