Winchester Ammunition says the explosion happened in a production area at its Oxford plant Tuesday. The company says it’s investigating the cause.

News outlets report at least three workers were taken to the hospital.

Lafayette County Sheriff’s Investigator Alan Wilburn says smoke filled the building and employees were evacuated. The company says some production continued.

Winchester is a subsidiary of Olin Corp. of Clayton, Missouri. It opened the $100 million Oxford plant in 2011.