Firefighters say they were able to contain a Thursday afternoon apartment fire to one unit, saving the other 19 and thus the building.
Crews responded to a complex near 16th Street and Thomas Road and arrived to find a working fire in a second-floor apartment.
The owner was inside at the time and was not injured, firefighters said.
Investigators remained on scene and were working to determine how it started as of 8 p.m.
Authorities did not immediately have an estimate of the damage.