Investigators are still working to determine what caused the spate of fires that broke out around Los Angeles last week, but residents fear electrical infrastructure may have sparked at least one of them.

According to the U.S. Forest Service, there have been more than 3,600 wildfires in California related to power generation, transmission and distribution since 1992. Some of the most devastating fires have been attributed to problems with utility poles and power lines.

CalFire publishes data on past large wildfires and determines their causes in various natural and human-related categories, such as lightning or arson. The agency lists more than 12,500 fires since the late 19th century, with the causes of more than half unknown or unidentified.

Lightning and equipment use are among the most common known causes, but in recent decades the proportion of fires known to be caused by energy infrastructure has increased across the state.

Residents of Altadena, California, sued Southern California Edison on Monday, saying the utility’s electrical equipment sparked the Eaton fire, which burned more than 13,000 acres and 5,000 buildings in the city and surrounding areas. The company said it was investigating the origin of the fire.

Power distribution lines have been found to have caused some of the largest fires in California in recent years.

The Thomas Fire in 2017 was sparked when high winds forced Edison’s power lines in Southern California to collide, a situation known as a “line strike.” Burning material fell to the ground in Upper Anlauf Canyon, about 35 miles from the current Palisades fire, and the resulting fire burned for nearly 40 days.

The 2018 Camp Fire in Northern California began when an electrical arc between one of Pacific Gas & Electric’s power lines and a steel tower spewed molten metal onto the vegetation below. This fire claimed more than 80 lives and destroyed over 18,000 buildings.

In the summer of 2021, California’s largest single wildfire, the Dixie Fire, broke out when a tree near the Cresta Dam in Northern California came into contact with several PG&E distribution lines. Power continued to flow on one of the lines, causing the fire to break out and burn nearly a million acres across four counties.

California isn’t the only state that has struggled with power-related wildfires in recent years. The largest wildfire in Texas, the Smokehouse Creek Fire, burned over a million acres in 2024.

Similar situations have also led to wildfires in Oregon. The 2020 Labor Day fires destroyed thousands of homes and killed at least nine people, in part because power was not turned off during high winds.