Mountain Fire latest: Wildfire scorches 20,000 acres in Southern California, destroying more than 130 structures

The Mountain Fire burns along a hillside as horses gallop in an enclosure at Swanhill Farms in Moorpark, Calif.
The Mountain Fire burns along a hillside near Swanhill Farms in Moorpark, Calif. (Noah Berger/AP)

A rapidly moving wildfire known as the Mountain Fire continued to grow north of Los Angeles on Thursday, destroying homes, forcing evacuations and prompting California Gov. Gavin Newsom to issue a state of emergency.

“This is a dangerous fire that’s spreading quickly and is threatening lives,” Newsom said in a statement.

A house burns in Camarillo, Calif., on Wednesday.
A house in Camarillo, Calif., on Wednesday. (Marcio Jose Sanchez/AP)

The blaze, which broke out in Ventura County on Wednesday morning, has scorched more than 20,000 acres, or about 32 square miles, destroying at least 132 structures and damaging 88 others as strong Santa Ana winds pushed it into neighborhoods in the Camarillo and Moorpark foothills.

The cause of the fire is unknown and remains under investigation.

As of Thursday evening, it was only 5% contained. But fire officials were optimistic that as conditions improved, they would be able to get it under control.

At a briefing on Thursday evening, Ventura County Fire Battalion Chief Nick Cleary said there was "no significant growth in the perimeter today."

A firefighter battles the Mountain Fire in Santa Paula, Calif.
A firefighter battles the Mountain Fire in Santa Paula, Calif., on Wednesday. (Noah Berger/AP)

Fire agencies from across Southern California are assisting with the Mountain Fire. More than 800 firefighters worked through the night battling the blaze, according to the Ventura County Fire Department, with more on the way.

“It was a significant 36-hour firefight,” Ventura County Fire Chief Dustin Gardner told reporters. “We had many firefighters out on the line until this evening. They fought fire for 36 straight hours. That’s a feat of human strength.”

Water-dropping helicopters were over the fire the entire evening on Wednesday and Thursday, which is not common, Gardner said.

First responders push a vintage car away from a burning home in Camarillo, Calif.
First responders near a burning home in Camarillo, Calif., on Wednesday. (Noah Berger/AP)

Evacuation orders were issued for more than 14,000 people, though it is unclear how many heeded them. At least 250 homeowners chose to stay, Ventura County Sheriff Jim Fryhoff said Thursday.

Ten people have been treated for smoke inhalation or other non-life-threatening injuries due to the fire, but no deaths or serious injuries have been reported.

Fire officials said that the evacuation orders for the impacted area would continue for several days before crews deemed it safe for people to return.

An air tanker drops fire retardant on the Mountain Fire near Fillmore, Calif.
An air tanker drops fire retardant near Fillmore, Calif. (David McNew/Getty Images)

The National Weather Service had issued a "particularly dangerous situation" red flag alert, warning of “widespread, extreme fire weather conditions” across Southern California through Friday morning.

But conditions are expected to improve as winds are forecast to subside before returning by the middle of next week.