(HANNIBAL)—Hannibal fire investigators say a fire Friday evening at 1521 Valley in Hannibal is accidental and electrical in nature. The alarm was turned in at 7:36 p-m and firefighters arrived to find heavy smoke and fire coming from the front of the house.  Fire crews contained and extinguished the fire in 20 minutes. The fire department says the house was not occupied at the time and that the structure sustained heavy smoke damage throughout and heavy fire and heat damage in the living room.