Fire investigators are working to determine the cause of a house fire that displaced two adults who are now receiving help from the American Red Cross. North Charleston firefighters responded to the fire at 4:18 a.m. in the 2300 block of Kent Avenue, Assistant Chief Christan Rainey said. The first crews to arrive reported heavy smoke and flames coming from the single-family home. Firefighters were able to extinguish the fire and made sure no one was still inside the home. Smoke alarms save lives, firefighters say. Make sure you have working smoke alarms in your home. Smoke alarms over 10 years old should be replaced. North Charleston Fire Department can install free smoke alarms in your home.