Fire investigators are trying to determine the cause of a fire that destroyed an elderly man’s home in Federal Way early Monday morning. South King County Fire & Rescue firefighters responded to the blaze at the residence in the 3700 block of Southwest 332nd Place shortly after 4:30 a.m. to find it engulfed. SKFR Capt. Jeff Bellinghausen said the single occupant to the home, a 90-year-0ld man, was at home at the time of the fire but was unable to tell firefighters how he was alerted to the fire or what may have caused it. The man escaped uninjured and went to a neighbor’s home and told the owner his house was on fire. The neighbor called 911.