How a Popular Science article led the ATF to this small-town Minnesota explosives maker

BROWNSVILLE, Minn. – On a recent afternoon in this small river town, a caravan of federal agents veered off the main drag, down a dirt road that leads into a valley of brown fields and farmland. They pulled up to a white house, tottering with age and isolated by hills and state forest land, where they'd come to arrest a man they say has been building explosives here for years.

Kenneth Miller, 58, faces felony charges for allegedly manufacturing, dealing and transporting highly combustible explosive material recovered that day. Agents from the Bureau of Alcohol, Tobacco, Firearms and Explosives also found three guns in the home, which Miller is forbidden from possessing due to his felony record, according to the criminal complaint. Miller's attorney declined to comment on the case.

Miller didn't do much to hide his business, Lightning Pyrotechnics. He has claimed to sell explosive products to big-name clients: the NFL, air shows, Hollywood movies, the military and foreign militaries.

Yet it was a national magazine article in Popular Science that led the ATF to Miller's secluded home that March day, according to a warrant recently unsealed.

In May — 10 months before the ATF raid — special agent Sara Thomas came across a headline on the New York-based magazine's website: "This pyrotechnics expert turned his Minnesota backyard into a DIY fireworks testing ground."

The article portrayed Miller as a mad scientist who harvests industrial material to build 50-pound rockets and magnesium fireworks that burn at 4,000 degrees and blow craters into his farmland.

It featured photographs of Miller shooting red flares off the hood of his pickup truck into the night sky and packing powdered chemicals in a nearby shack he used as a makeshift laboratory. It said Miller's smoke bombs are used as car-crash effects in action movies, including the blockbuster "Transformers" franchise. "His personal pyrotechnic experiments don't belong on the 50-yard-line or in anyone's backyard," reads the article.

Authorities tell a darker story about Miller. They say past felony convictions for building explosives in the 1980s prohibits him from touching these materials.

Miller has also terrorized the neighbors by shooting flares late at night, and his products have been implicated in accidents that maimed a customer and killed an employee, according to court and police documents and a lawsuit.

The ATF would not comment on the case, other than to say the department "investigates violations of federal explosives laws as expeditiously as possible to gather the facts needed for successful prosecution."

Brownsville is a town of just more than 500 people that runs along the Mississippi River, on the eastern edge of the state adjacent to La Crosse, Wis.

Miller lives off a county road in the Freeburg Valley, surrounded by a state-protected forest. He manufactured the explosives just a couple miles from his home, atop a steep dirt hill called Gopher Trail, in a brown-and-white shack, according to charges.

The ATF raid on March 3 wasn't the first time law enforcement officials had come to his doorstep with questions about explosives.

In 2004, investigators from the Houston County Sheriff's Department called on Miller after an anonymous tip that Miller had been making fireworks. When they got to the property, they found red powder residue, 55-gallon drums and cardboard bearing the title "Pyrotech."

Miller told them he'd been manufacturing smoke products, a procedure that entailed standing in his yard wearing a mask and gown. He'd noticed a few passersby slow down agog, and he "knew it was only a matter of time before law enforcement would be stopping by," according to police reports.

Miller also told the officers about his criminal history: convicted of a felony in 1986 for conspiracy to make illegal explosives in Texas; convicted again of illegally possessing a firearm a few years later in North Dakota. He now used legal chemicals to make flares and smoke bombs, Miller told them, and he showed the deputies a garage with a galaxy of chemicals and dyes.

The Sheriff's Office would return here several times in the coming years on reports of fireworks and flares flying above the tree line. In March 2019, the Department of Natural Resources came to investigate a wildland fire in the state forest surrounding Miller's home.

Miller first denied knowing anything about how the fire started, according to incident reports. After investigators found parachutes in the trees, Miller admitted that his teenage son was shooting off a 12-gauge flare gun he'd been preparing for a customer.

The DNR billed Miller $350 for fire suppression costs last May. Miller apologized and offered to a put on a demonstration for the local fire department on magnesium and pyrotechnic fires.

The same month, Popular Science published the profile on Miller, which arrived on the desk of agent Thomas.

In researching his past, Thomas discovered a 2011 lawsuit in Tennessee naming Miller and Lightning Pyrotechnics. The lawsuit alleged one of Miller's smoke bombs blew a man named Perry Richardson "from his feet and onto his back, and blew shrapnel through and into his eye," leaving Richardson with one eye.

The explosion blew through Richardson's abdomen and stomach, and "caused serious burns to his leg, groin, face and stomach," according to the complaint. "The explosion and shrapnel from [Miller's] product caused extensive hospitalization, medical flight transportation by helicopter, skin grafts, multiple and extensive surgeries, extensive physical therapy, scarring, loss of use and permanent physical disabilities, along with severe emotional pain and suffering, including flashbacks, anxiety, depression and insomnia."

Thomas called the Houston County Sheriff's Department and talked to investigators who said they were "very familiar" with Miller's explosive work after years of complaints from community members; the Coast Guard had even expressed concern after calls from boaters on the river who saw Miller shooting off flares in the middle of the night.

Thomas also looked into the death of one of Miller's former employees, mentioned briefly in the Popular Science article. In 2000, the ATF had investigated an explosion in North Dakota involving Miller and a man named Howard Snelson. Miller had been left badly burned. Snelson "died as a result of the explosion due to smoke inhalation and thermal burns," according to Thomas' warrant unsealed last month. In an interview with police a few years after the explosion, Miller said Snelson was his best friend and business partner.

The ATF searched Miller's house and makeshift laboratory in June, a month after Popular Science published the article. In March, about a dozen ATF cars and local sheriff's deputies drove up to his house to arrest him.

Miller now faces four felonies for illegally possessing explosives and firearms. In a hearing in late March, he admitted to using meth and violating several rules of a halfway house at which he'd been ordered to stay.

He is now awaiting criminal trial in Sherburne County jail.