How did the California wildfires start? Officials weigh power lines, fireworks – and arson

On January 15, 2025By Littum

Upper line

Four catastrophic wildfires were still burning in Los Angeles and Ventura counties in Southern California on Tuesday, but it is not yet clear what started the blazes – as officials, lawyers and experts weigh theories such as electrical problems, embers from older fires and arson.

This photo provided by Patrick Dossett shows the start of the Palisades Fire in Southern California, … (+) Tuesday 7 January 2025.

Associated Press

Key facts

The Palisades Fire and Eaton Fire both broke out on January 7 and grew to more than 23,000 and 14,000 acres, respectively, destroying thousands of structures and prompting more than 100,000 evacuations across Los Angeles.

Several smaller fires — including the Hurst Fire and Auto Fire, both of which were still active as of Tuesday — broke out after the Palisades and Eaton fires and prompted multiple evacuations.

The California Department of Forestry and Fire Protection indicates that the causes of all four active fires are still under investigation, leading to unanswered questions about what could have caused some of California’s most destructive wildfires.

Anonymous officials involved in the investigation into the origin of the Palisades fire said Los Angeles Times it appears to be of human origin, although they noted that the investigation is ongoing.

Investigators are focusing on a “crime scene” area spanning most of Los Angeles in a neighborhood of rocky bluffs and popular hiking trails as the potential ignition point for the Palisades fire, New York Times reported.

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Arson

Dominic Choi, the assistant police chief of Los Angeles, said Monday that officials are investigating all angles and are not ruling out arson as the cause of any of the large fires, but he added that there is “no final determination that it is attached.” The theory has attracted public attention after a wave of arson-related arrestsincluding an arrest of a man who was allegedly seen lighting a fire near the smaller Kenneth Fire last week – although police later said there was no probable cause to charge him with arson and they cannot confirm any link between the arrested and the fires. Some experts are skeptical of the theory. A former battalion chief of the Los Angeles Fire Department said so NBC News the area where the Palisades fire began is “inaccessible, rugged terrain” that would not typically attract an arsonist. Experts also told NBC that natural causes are a more plausible theory because of the high wind conditions: “Most of the time these fires are not set … There is no data to support wind bringing out arsonists,” a former LA County Sheriff’s Office detective said. The National multidisciplinary fire center says that arson may account for more than 20% of human-caused wildland fires, but the actual number is unclear, as arson can be misclassified for some time.

Power lines and electrical infrastructure

Several Altadena residents sued Southern California Edison on Monday, alleging the Eaton fire was started by the company’s electrical equipment. The lawsuits cite eyewitness reports of sparking power lines. The company has pushed back against the theory, saying in a declaration Sunday, its “analysis shows no outages or operational/electrical irregularities in the 12 hours before the reported start time of the fire until more than one hour after the reported start time of the fire.” One of the complaints filed reportedly alleged, “there is clear evidence from video footage, photographs and witness accounts that the fire was caused by electrical equipment operated by defendants Edison International and Southern California Edison.” Power infrastructure has historically been a leading cause of fires in California — with eight of the state’s 20 most destructive fires having power-related causes — and the number of fires started by equipment has grown recently, New York Times reported.

Old embers – or fireworks

Some experts and residents believe the Palisades fire may have been started by the remains of a New Year’s Day fire that began after fireworks were set off. The Jan. 1 fire broke out in the same location as the Palisades fire and burned about three to four acres before fire officials said it was contained about five hours later. Associated Press reported. Michael Gollner, a fire researcher and professor at the University of California at Berkeley, told The Washington Post “it’s certainly possible that something from the previous fire, within a week, had reignited and caused the ignition” of the Palisades fire. A spokesperson for the Los Angeles Fire Department confirmed that the department does not typically patrol past fire scenes for still burning embers. The The New York Times notes a number of previous large fires were determined to have been started by old flames that officials thought were out, including the 2023 wildfire in Maui that killed 102 people and a deadly 1991 firestorm in Northern California.

Other human causes

Cal Fire said 95% of California’s past wildfires have been caused by humans, but the agency noted that human causes range from intentional arson to accidental situations, such as campfires or discarded cigarette butts. CNN reported.

Lightning

Officials were able to rule out lightning as a potential cause of the Palisades or Eaton fires since the area did not experience stormy weather the week the fires started, ABC News reported on January 9. However, lightning is a common cause of wildfires and led to 174 wildfires in Southern California in 2023, according to National multidisciplinary fire center.

How many other fires were there in Los Angeles?

In addition to four active wildfires in Los Angeles and Ventura counties, there were at least four other fires that are now contained, including the Sunset Fire burning through the Hollywood Hills and Runyon Canyon, the Kenneth Fire in the West Hills Area, the Lidia Fire in the Angeles National Forest and the Woodley Fire.

What to look for

More information from the investigators. The process of identifying the cause of a fire begins with pinpointing the fire’s starting point, after which investigators will usually search the scene on their hands and knees looking for clues as to what might have started it, which can take days. NBC News reported. If they find evidence that it was started by an individual, investigators will then have to determine whether it was intentional arson or accidental negligence, but NBC reported that the process could take months or years.

Key background

Regardless of the cause of the fires, experts seem to agree that the conditions for the fires to spread easily were exacerbated by climate change. California Air Resources Board said the area burned by wildfires in the state has increased every year since 1950, and unusually warm temperatures combined with very low rainfall create “conditions for extreme, high-severity wildfires that spread rapidly.” Last summer was particularly hot in California and across the West, while there was very little rainfall: The BBC reported that downtown Los Angeles has received only 0.16 inches of rain since October.