A stuck gas valve is thought to be the cause of the fire at this Mason City plant.

Operations are expected to be back to normal later today after a fire Monday at a Mason City egg processor.

Firefighters were called shortly before 10 o’clock Monday morning to Cargill Kitchen Solutions after a fire broke out, causing thick black smoke to pour out of the facility.

Mason City Fire Marshal Mark Christiansen says a gas valve apparently stuck, causing filters on a rooftop heating element to be ignited. Cargill spokesman Tim Loesch said the cleanup at the plant started Monday afternoon after firefighters left, and operations were expected to fully resume Tuesday morning.

The plant employs 181 workers in three different shifts.

By Bob Fisher, KLSS/KRIB, Mason City

Radio Iowa