The Eastern Jackson County Courthouse in Independence was closed Tuesday afternoon after a malfunctioning exhaust line set off a carbon monoxide detector.
Courthouse employees, attorneys, jurors and other occupants evacuated the building shortly after 12:15 p.m., the county said in a release.
Independence firefighters determined an exhaust line for the boiler on the third floor was not venting properly. After fixing that, officials started doing air quality testing before anyone re-entered.
About 2 p.m., people gathered in the parking lot across the street received word the building had been closed for the day and court proceedings were canceled.
The county says the courthouse will open as normal Wednesday.