(Centralia, WA)  --  Authorities say a small fire was ignited at a home in Lewis County, as a resident was using a homemade flamethrower to combat a cockroach problem.  Fire officials say crews were dispatched yesterday morning to a home in Centralia, but the resident had extinguished the flames by the time they arrived.  Investigators say the resident was using insect spray and a lighter to create a flamethrower to kill the cockroaches, and started the blaze.  No one was injured.