'Illegal Activity' Found During Probe of Deadly Esparto, CA, Fireworks Plant Blast

SACRAMENTO, Calif. — California’s Office of the State Fire Marshal has completed its investigation into the deadly fireworks explosion in Esparto, and uncovered evidence of “illegal activity” and criminal wrongdoing, the agency announced Monday.

The findings have been provided to the Yolo County District Attorney’s Office, which has been conducting a far-reaching criminal probe into the fireworks operation that exploded in the rural community, killing seven people and igniting a 78-acre wildfire.

“Our Arson and Bomb investigators have compiled a report that reflects the Office of the State Fire Marshal’s commitment to uncovering what happened in Esparto,” California State Fire Marshal Daniel Berlant said in a press release. “This complex investigation took many turns as new information emerged, but the team diligently followed leads and gathered the facts that form the basis of the report.”

In a statement the Yolo County D.A.’s office said that Cal Fire was “sending its reports.”

“The investigation and review is ongoing. That’s all we have for now,” the statement said.

The investigative focus had been the cause of the deadly blast. The agency – a division of the California Office of Forestry and Fire Prevention, or Cal Fire – initially anticipated that their investigation would conclude in August, but the case proved more complicated than expected, Berlant told The Bee in November. The report’s public release will be up to the D.A.’s discretion.

The criminal investigation into the Esparto fireworks operation remains ongoing. The investigation has so far led to multiple arrests and dozens of search warrants.

In the aftermath of the Esparto tragedy, Cal Fire itself has come under scrutiny for missing apparent warning signs about Devastating Pyrotechnics, one of the two companies that operated on the Yolo County property. Records obtained by The Bee found that the state agency was made aware of the company’s possible ties to illegal fireworks operations following a May 2025 seizure in Commerce, California and a 2023 explosion in San Jose, but never looked into the company’s operation in Esparto.

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