BROWNSVILLE, Minn. (AP) — A magazine article has landed a Minnesota explosives manufacturer in big trouble with federal prosecutors.

Kenneth Miller of Brownsville was indicted Feb. 25 on charges of manufacturing, selling and transporting explosives as well as being a felon in possession of explosives and firearms. He pleaded not guilty Wednesday.

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The La Crosse Tribune reports the federal Bureau of Alcohol, Tobacco, Firearms and Explosives began investigating Miller after seeing a May 2019 “Popular Science” article titled “This pyrotechnics expert turned his Minnesota backyard into a DIY fireworks testing ground.” The article included a photo of Miller launching a signal flare off the hood of his truck. The caption said he buys his devices from industrial suppliers and harvests their parts for his own projects.

Harvesting the innards of flares and using them to make explosives that are later sold is illegal.

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The Minnesota Department of Natural Resources launched its own investigation into Miller in March 2019. A fire occurred near his property and an investigator saw numerous parachutes like the ones used in Miller’s rockets in the trees where the fire started and on Miller’s land.

Miller’s attorney, listed in court records as James Ventura. didn’t immediately respond to a message seeking comment Saturday.

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