A fire caused $40,000 in damage to an apartment building and displaced some occupants Wednesday night.
The Janesville Fire Department said it was dispatched for a report of a fire at a three-unit apartment building at 156 S. Cherry St. at 9:24 p.m.
Firefighters arrived to find a two-story wood-frame building with smoke coming from the front upper apartment.
Fire officials said a space heater had been left running while the occupant was gone and the heater caught nearby combustibles on fire.
Firefighters were able to contain the fire to the upper front apartment.
Smoke damage occurred to the rear upper apartment, and water damaged occurred to the lower apartment, according to a Janesville Fire Department news release.
All occupants got out safely before firefighters arrived.
A tenant in another apartment discovered the fire after being alerted by the second-floor smoke detector sounding and seeing smoke on the second flood.
The upper apartment occupants were displaced due to fire and smoke damage, fire officials said.
Damages are estimated at $40,000 to the structure and $10,000 to the contents.
One firefighter was injured with a back strain during firefighting activities, according to the news release.