Mr. Swanton said authorities didn't yet know if the fire and the subsequent explosion was an accident or intentionally set, according to the Associated Press.

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He said the explosion was a "tragic accident" resulting from a "risk that was identified".

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Authorities have said investigations are under way to determine whether the explosion was the result of an accident, negligence, or an attack.

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At first, officials assumed the explosion on a chilly day was an accident.

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Some residents spoke to Forbes at the time, describing the accident as resembling the infamous Challenger explosion, and adding that Blue Origin remains something of a mystery even locally.

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The charges related to an attempt to destroy documents after the explosion and making false statements to federal agents investigating the accident.

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In the case of the Texas explosion, it's possible that it was simply a horrific accident, although authorities say they are treating the area as a crime scene until they have firm evidence to the contrary.

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Authorities had said earlier there was no indication that the explosion and the fires that preceded it were anything other than an industrial accident.

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