Authorities are investigating multiple possible causes behind the massive wildfires that have claimed at least 11 lives and ravaged thousands of homes and commercial properties in the Los Angeles region.
In the affluent, hillside neighborhood of Pacific Palisades, where Hollywood icons like Jamie Lee Curtis and Billy Crystal saw their homes destroyed by the fire, officials have traced the blaze's origin to an area behind a residence on Piedra Morada Drive, perched above a heavily wooded arroyo.
What can be the two primary causes
The National Fire Protection Association notes that whilst lightning typically causes most fires in the United States, investigators quickly eliminated this possibility.
No lightning activity was recorded near the Palisades area or around the Eaton Fire zone in eastern Los Angeles County, where hundreds of properties were also destroyed.
The next two primary causes are deliberately set fires and those caused by utility lines. However, neither fire has been officially confirmed as arson, nor have utility lines been verified as the source.
According to John Lentini, proprietor of Scientific Fire Analysis in Florida and investigator of significant California fires including the 1991 Oakland Hills Fire, the extensive nature of the blaze does not alter the investigative methodology.
"This was once a small fire," Lentini said, Associated Press reported.
"People will focus on where the fire started, determine the origin and look around the origin and determine the cause," Lentini added.
2017 Thomas Fire, amongst California's largest
Terrie Prosper, communications director at the California Public Utilities Commission, explained via email that utilities must report any "electric incidents potentially associated with a wildfire." CPUC staff subsequently investigate for possible legal violations.
Investigators determined that the 2017 Thomas Fire, amongst California's largest, began when Southern California Edison power lines made contact during strong winds. This incident resulted in two fatalities and burnt over 440 square miles (1,140 square kilometres).
Southern California Edison submitted a report to the CPUC regarding the Eaton Fire near Pasadena on Friday.