Fire investigators have completed their probe into the cause of a fire that destroyed a home in Hawaii Kai Thursday night.  The fire on Hanamaulu Street was classified as accidental. It began in a back bedroom and was caused by a malfunctioning gas torch that was being used to light candles.  It was reported just after 10:30 p.m. on Hanamaulu Street. Several fire companies responded and found the home fully engulfed in flames when they arrived. No one was injured, but five people were displaced.  The fire was controlled just before 11 p.m.  Damage was estimated at $581,000.