MADISON, Wis. (AP) — A federal jury has convicted two senior employees at a Wisconsin corn plant of falsifying records and obstructing an investigation into a fatal corn dust explosion in 2017, Justice Department officials announced Oct. 17.

Corn dust is explosive, and high concentrations are dangerous. Federal regulations require grain mill operators to perform regular cleanings to reduce dust accumulations that could fuel a blast.

Jurors found Derrick Clark, vice president of operations at Didion Milling, and Shawn Mesner, a former food safety superintendent at the company, guilty of multiple safety, environmental and fraud charges on on Oct. 13. The two men are the latest in a growing list of Didion employees found guilty in association with the 2017 explosion that killed five people at the company`s Cambria corn mill.

Didion Milling pleaded guilty in September to charges that its employees falsified environmental and safety compliance records for years leading up to the explosion. The company agreed to pay a $1 million fine and $10.25 million to the estates of the five workers who were killed.

Clark was convicted of making false Clean Air Act compliance certifications and lying to investigators during a deposition. Mesner was found guilty of conspiring to mislead Occupational Safety and Health Administration investigators by lying on sanitation records that tracked cleanings meant to remove corn dust from the mill.