(LOS ANGELES) — The Bobcat Fire, the massive blaze burning through the Angeles National Forest, was likely ignited by tree branches that fell onto a power line, according to Southern California Edison.

The U.S. Forest Service, which is conducting the probe into the origin of the fire, has retained a section of an overhead conductor line and three tree branches from an area near where the fire first sparked, the utility company wrote in a letter to the California Public Utilities Commission on Monday. However, federal investigators have not shared the details of the investigation with SoCal Edison, the company wrote.

The blaze began on Sept. 6 near the Cogswell Dam on the west fork of San Gabriel Canyon in the Angeles National Forest, according to officials.

At the height of the fire, smoke filtered into Los Angeles from the mountains. It is currently 92% contained and has scorched more than 115,000 acres, destroying 171 structures.

The West Coast has seen a record number of massive fires in 2020. At least four dozen large uncontained wildfires are currently burning.

After a brief respite in weather conditions, a heat wave and gusty, offshore winds are now creating critical fire danger from California to Colorado. Most western states are under some sort of wind, fire or air quality alert.

A heat advisory has been issued for Southern California for the second day in a row for temperatures to be in the 90s and even 100s for some inland areas.

Many of the fires in California this season began with a series of lightning strikes in the Bay Area in mid-August, but dozens of people in the state have also been arrested for arson.

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