Sioux City, IA — A Sioux City apartment complex was evacuated Monday afternoon for carbon monoxide.
Sioux City fire crews arrived just after 12:00 p.m, at the Stellart Apartments on 21st and Nebraska for an alarm.
Firefighters found unsafe levels of carbon monoxide and evacuated the building. The residents were kept warm on a city bus.
Crews say that the cause was a worker using a cement cutter in the basement without proper ventilation.
Residents were allowed back in their apartments an hour later.
One person was treated on the scene.