(AP) — Helped by cooler temperatures, firefighters gained ground Friday against three blazes in Southern California and authorities began scaling back evacuation orders that displaced thousands of people.

The largest blaze is the Bridge Fire east of Los Angeles, which has burned 81 square miles (210 square km), torched at least 33 homes and six cabins and forced the evacuation of 10,000 people. The cause of the fire is not yet known. After days of burning without fire crews being able to stop its forward march, it was 3% contained on Friday.

“Firefighters made great progress on the ground, aided by aircraft to attack the fire aggressively 24 hours per day,” the California Department of Forestry and Fire Protection said in a statement about the blaze.

While firefighters have made significant progress, the three major wildfires that have ravaged the mountains east of Los Angeles, destroying dozens of homes, injuring a dozen people, and burning more than 100,000 acres (40,470 hectares), still pose significant threats to some communities.

California is entering the height of wildfire season and has already seen nearly three times as much acreage burn as during all of 2023.

Evacuation orders were being scaled back, including in parts of Big Bear where the Line Fire forced thousands of people to flee after authorities say a delivery driver purposely started the blaze on Sept. 5.

The fire has charred 59 square miles (153 square km) in the San Bernardino mountains where Southern California residents ski in the winter and mountain bike in the summer. It was 21% contained as of Friday.

The Line Fire is burning through dense vegetation that grew after two back-to-back wet winters that included snowstorms that caused tree branches to break, leaving behind a lot of “dead and down fuel,” said Cal Fire Operations Section Chief Jed Gaines.

The Big Bear Zoo had to move all its animals to a zoo in the city of Palm Desert to protect them from the wildfires and escalating temperatures, zoo officials said.

The fires have threatened tens of thousands of homes and other structures across Southern California since they escalated during a triple-digit heat wave. Weekend forecasts called for temperatures that reached triple digits last weekend to drop to the 70s.

The cooler weather that started mid-week was helping firefighters slowly gain the upper hand in battling the blazes. No deaths have been reported, but at least a dozen people, mainly firefighters, have been treated for injuries, mostly heat-related, authorities said.

Jason Anderson, district attorney for San Bernardino County, said Thursday that nine arson-related charges have been filed against Justin Wayne Halstenberg, who is accused of starting the Line Fire.

Anderson said Halstenberg, 34, attempted to start three fires within an hour in the city of Highland. Two fires were extinguished by firefighters and a good Samaritan. Officials said the third fire that Halstenberg started became the Line Fire.

“This is particularly galling in a community that unfortunately over the last couple of years has dealt with the scourge of wildfires,” he told reporters, adding that the suspect’s vehicle has been linked to three areas where the fires were started.

Halstenberg is due to be arraigned in court on Monday, the San Bernardino County District Attorney’s Office said. The office said Friday it didn’t have information about an attorney for Halstenberg.

Halstenberg’s mother, Connie Halstenberg, told the Los Angeles Times that her son “did not light that fire.”

The full extent of the damage caused by the wildfires remains unclear but Anderson said at least one home has been destroyed by the blaze.

Further south, the Aiport Fire burning in Orange and Riverside counties has burned more than 37 square miles (96 square kilometers). The fire, which was reportedly sparked by workers using heavy equipment, was 8% contained Friday morning.

Ten firefighters and two residents were injured in the blaze, according to the Orange County Fire Authority. The fire has been difficult to tame because of the steep terrain and dry conditions — and because some areas hadn’t burned in decades. It has destroyed at least 27 cabins in the Holy Jim Canyon area, authorities said.

In northern Nevada, the worst danger appears to have passed near Reno, where a wildfire on the Sierra’s eastern front forced 20,000 evacuations over the weekend. Most of the remaining evacuations were lifted for the Davis Fire, which has burned nearly 9 square miles (23 square kilometers) of timber and brush. Containment was estimated Friday at 56%.
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Rodriguez reported from San Francisco. Associated Press reporters Amy Taxin in Santa Ana, California, and Scott Sonner in Reno, Nevada contributed.