The police Arson Squad is investigating a fire which gutted a house in Gosnells this morning.
The fire, which started at 3.13am at an unoccupied property in Verna Street, caused extensive damage estimated to be worth about $250,000.
The blaze took 16 fire crews two hours to extinguish.
A Department of Fire and Emergency Services spokesman said the fire was believed to be deliberately lit.
Anyone with information is asked to contact Crime Stoppers on 1800 333 000.