FILE - In this May 14, 2010 file photo, rescue vehicles stand outside a gunpowder plant after an explosion at the plant killed two people in Colebrook, N.H. The owner of the Black Mag plant, Craig

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FILE - In this May 14, 2010 file photo, rescue vehicles stand outside a gunpowder plant after an explosion at the plant killed two people in Colebrook, N.H. The owner of the Black Mag plant, Craig Sanborn, 64, of Maidstone, Vt., was convicted of negligent homicide on Wednesday, Oct. 23, 2013. (AP Photo/Steve Legge, File) less 

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Associated Press
Thu, Oct 24, 2013 12:44 PM EDT