Los Angeles, Nov 2 (AFP) A new wildfire in California grew to nearly 9,000 acres (3,700 hectares) on Friday, sending thousands of people fleeing and further stretching resources in a state struggling with a spate of wildfires this season.

The so-called Maria Fire erupted Thursday evening in Ventura County, 65 miles (105 kilometers) northwest of Los Angeles, and burned out of control through the night, driven by high winds and threatening 2,300 structures.

By Friday afternoon, the wind-fueled blaze that risked consuming citrus and avocado orchards as well as other crops was zero percent contained. Authorities said 8,000 people were under evacuation orders and at least two structures had been burned.

Ventura County Sheriff Bill Ayub said fire crews had been thwarted by people flying drones in the area.

"Last night and early morning we had individuals flying small drones in the area of the flight operations for the fire suppression," he told a media briefing.

"This creates a very significant hazard for our airborne fire fighting assets and causes them to land and stop firefighting efforts as long as that aircraft is in the area."

The Maria Fire erupted as crews continue to battle multiple blazes that have broken out across the state in the last two weeks, prompting massive evacuations and power cuts.

Another fire, the Easy Fire, which broke out Wednesday in Ventura County and came dangerously close to the Ronald Reagan Presidential Library, was almost fully contained on Friday.

"We're in the middle of a big fight, and we're about a week into this and the end is not yet in sight," Ventura County Fire Chief Mark Lorenzen told reporters Friday afternoon.

"It has been an uphill battle ever since." Up in Sonoma County, north of San Francisco, there was some good news as authorities reported that the Kincade Fire, the largest in the state this season, was 68 per cent contained.

The devastating fires that have exploded across the state this season were addressed by teen climate activist Greta Thunberg on Friday as she spoke at a rally in Los Angeles to pressure California lawmakers to pass stricter environmental policies.

"Today, in California, we can see the wildfires happening just around the corner, wildfires that are being intensified by the climate crisis," the 16-year-old Swede said.

"But it's not just here. Everywhere around the world, we can see these horrible environmental impacts that countless people are suffering and dying from." The fires prompted California Governor Gavin Newsom to declare a statewide emergency this week.

The flames have been fed by bone-dry conditions, especially in the lower part of the state which has not had rainfall for months.

An extreme red flag warning issued for the Los Angeles area this week was lifted Thursday but the National Weather Service warned that so-called Santa Ana winds could still wreak havoc through Saturday evening.

In a bid to reduce the risk of wildfires, the state's largest utility company, Pacific Gas & Electric, has been shutting off power to millions of customers in northern and central California, prompting outrage.

The blazes come as California is still reeling from the aftermath of the most destructive wildfire in state history -- the Camp Fire, which destroyed the town of Paradise and killed 86 people last year.

Similar blazes in northern California, including in the Napa and Sonoma wine regions, killed 44 people in 2017 and destroyed thousands of structures.

There have been no fatalities linked to this year's fires. (AFP)

(This is an unedited and auto-generated story from Syndicated News feed, LatestLY Staff may not have modified or edited the content body)