Fire officials released a statement on Tuesday, saying investigators have determined that the blaze was caused by an illegal cooking fire at an encampment in a brush area adjacent to where Sepulveda Boulevard crosses under the 405 Freeway.
VIDEO: Skirball Fire destroys homes near Getty Center
The Skirball Fire, which erupted last Wednesday in the Sepulveda Pass near the Getty Center, burned 422 acres of grass and brush, destroyed six homes and damaged 12 others in the Bel Air area.
The fire is currently 85 percent contained with 69 fire personnel still working on scene to achieve 100 percent containment, LAFD officials said.
PHOTOS: Skirball fire burns in the Sepulveda Pass near Getty Center
The blaze triggered evacuations, road and school closures in the area. All mandatory evacuations and road closures have since been lifted, fire officials said.
Mayor Eric Garcetti declared a local state of emergency in response to the Skirball Fire, as he had done in connection with the Creek Fire near Sylmar and Lake View Terrace.