The bombs that ripped through the crowd at the Boston Marathon, killing three people and wounding more than 170, were fashioned out of pressure cookers and packed with metal shards, nails and ball ... more 
The bombs that ripped through the crowd at the Boston Marathon, killing three people and wounding more than 170, were fashioned out of pressure cookers and packed with metal shards, nails and ball bearings, a source says. (April 16) less 
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Tue, Apr 16, 2013 4:05 PM EDT