According to Reuters, the Ventura County Fire Department determined a cause for the deadly Thomas Fire, which sparked in 2017.
The fire killed two people and destroyed over 1,000 structures northwest of Los Angeles.
Ventura's fire department determined that power lines owned by Southern California Edison sparked the deadly fire.
The investigation determined that the fire's origins traced back to high winds, which caused two power lines to collide.
The lines created electrical arcs between each other, causing the cables' physical material to ignite.