Inmates were evacuated from a work release center early Tuesday after smoke was spotted inside the building.
Firefighters responded to the Orange County Work Release Center, located at 130 West Kaley Avenue, after they received a call for smoke and a burning electrical odor.
Security personnel and Orlando Police evacuated the building, which included several dozen inmates dressed in pajamas, around 2 a.m.
While the inmates were being held in a fenced area, firefighters investigated the cause of the smoke.
After 30 minutes, firefighters found a belt in an air conditioning unit to be at fault for the alarm.
Inmates were allowed to return inside after firefighters cleared the building.