An overnight three-alarm fire in Post Falls burned through several apartments, displacing residents from those units. The fire started about 1:40 a.m., and burned from a second-floor balcony in building No. 1 of the Falls Park Apartments into the third floor, said Shaena Dunn, firefighter and public information officer for Kootenai County Fire and Rescue. Investigators later determined that an unattended cigarette was what triggered the fire, Dunn said. Firefighters were able to stop the fire from spreading to other buildings in the complex at 304 W. Fourth St.,and fire walls within the building helped contain damage and kept flames from spreading horizontally, Dunn said. It took about an hour to knock down the worst of the fire, she said. Three apartments were a complete loss and two had heavy fire damage. Others had smoke damage. In all, about 41 residents were evacuated. Red Cross was responding for emergency assistance. More than 30 firefighters from KCFR, Northern Lakes, Hauser and Coeur d’Alene fire departments responded in a dozen rigs. No injuries were reported.