STUTTGART, Ark. (AP) — Three Riceland Rice employees were injured, none seriously, in an explosion at a Riceland plant in Stuttgart, according to company spokesperson Kevin McGilton.

The employees suffered minor injuries that were not life-threatening in the Thursday blast that damaged the building, McGilton told the Arkansas Democrat-Gazette.

McGilton said the blast is under investigation but appears to be the result of an undetermined spark igniting accumulated grain dust in a building that is used to store rice.

The building uses equipment to reduce the amount and capture the dust and remove it from the air, but said the dust is “just one of the hazards of handling rough grain.”