LOS ANGELES, Oct. 9 (Xinhua) -- More than 20 wildfires erupted from Sunday night to Monday in California, killing 10, seriously injuring at least two, destroying at least 1,500 structures and forcing over 20,000 people to evacuate by Monday afternoon.

"There have been three confirmed fatalities, but I don't have a number of injures," Daniel Berlant, assistant deputy director of California Department of Forestry and Fire Protection (Cal Fire), told Xinhua Monday afternoon, adding that the cause of the fires remains under investigation.

The CA Statewide Fire Summary signed by Berlant at noon said "overnight significant winds fanned over a dozen fires across Northern California. 15 new wind whipped wildfires in eight countries have already burned over 73,000 acres (about 29,543 hectares) in the past 12 hours."

Meanwhile, Sonoma County Sheriff's Office tweeted that an additional seven fire-related deaths had been confirmed. "The focus continues to be the evacuations of thousands of residents and protecting property," Berlant said.

California Governor Jerry Brown has declared a state of emergency in Napa, Sonoma and Yuba counties, due to the effects of the multiple fires, which have damaged 1,500 structures, threatened thousands of homes and caused the evacuation of more than 20,000 residents.

California Highway Patrol said on its official website that it's Golden Gate Division Air Operations rescued 42 people ranging from 5 to 91 years old from the wildfires and the rescue operations are continuing.

Photos posted online by local residents showed that numerous buildings are on fire in downtown, some residences were burned to the ground, power lines fell down, two hospitals in the city "are no longer operational and patients have been evacuated."

"We are trying to just keep the roads clear for the firetrucks to get through because there are only two-lane roads through the valley. Smoke is everywhere. The smoke is very thick and very dangerous," John Taylor, the testing room manager of Yao Family Wines told Xinhua.

"Yes, it's smoky, and the air quality is poor," Kelli Cox, a resident of Napa city, located 5 miles (8 km) from the nearest fire scene, told Xinhua, adding that "we are leaving now to head south, we are leaving voluntarily in about 10 minutes."

Authur Walsh, chief editor of Food and Beverage World Magazine who lives in Sonoma, said: "The fire is not contained yet. Lives will be changed but the strong people of our county will endure."

When Northern California suffered the wildfires, a raging wildfire erupted Monday noon near Los Angeles at the same time, scorching 500 acres (202 hectares) in three hours and threatening more than 1,000 houses and forced about 200 residents to evacuate.

The evacuation order was applied 50 miles (80 km) east of downtown Los Angeles, where many tourists in Disneyland posted their pictures on Facebook, showing the sky turned to orange.

KTLA news channel said the fire erupted during the fall's first significant blast of Santa Ana winds, the seasonal gusts linked to some of Southern California's worst wildfires.