Investigators determined the explosives used were crudely made bombs, built into pressure cookers using black powder explosive and made more lethal by using nails and pellets, a lawmaker said.

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The bombs appeared to have been built by packing the pressure cookers with a black powder explosive as well as nails and pellets to maximize casualties, a lawmaker briefed by investigators said.

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The rest is likely to be less-explosive powder intended to produce color effects.

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According to the criminal complaint, police were called to a Texas residence on Tuesday where they discovered bomb-making components including a galvanised metal pipe, fuse, lighter and explosive powder in bags.

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The discovery of fireworks in the backpack is significant because the FBI found that the bombs were believed to contain a "low explosive powder extracted from commercial fireworks, " according to an FBI lab analysis reviewed by The Wall Street Journal.

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His many other inventions -- including explosive materials like the smokeless powder Ballistite -- were used for militaristic, mining, construction and other industrial purposes.

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But as long as those living in and around the region watch its conflicts from starkly opposing viewpoints, the old powder-keg will retain every speck of its explosive power.

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At that point they'll reduce the need for rooms full of powder charges and the associated dangers that come along with explosive shells, but will instead need to make way for what looks to be a warehouse full of capacitors.

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