Pawnee Fire in Lake County has burned 13,500 acres

CLEARLAKE OAKS, Calif. -- More than 2,000 firefighters are battling the Pawnee Fire in Lake County, which has already burned 13,000 acres with just 25 percent containment.

At least 22 structures have been destroyed and 600 remain threatened, and there's a mandatory evacuation order for the Spring Valley community.

Fire departments from around the Bay Area, including Alameda County, Berkeley, Fremont, Hayward and Oakland, have sent crews to battle the blaze.

Evacuation orders have been issued for the Double Eagle Ranch area. Officials say there is "significant fire activity" threatening the area, so residents have been strongly advised to get out now.

A shelter has been established at Lower Lake High School and will accept animals.

Authorities added that there is an alternative evacuation site at the Moose Lodge, which is located at the junction of Highway 53 and Highway 20. The lodge, which has a bar, restaurant and can handle animals, is very popular with locals when fires break out.

Officials are encouraging anyone in the area to conserve water so that firefighters can use it to fight the fast-growing blaze.

There are multiple road closures in and around the Spring Valley subdivision. More than 20 engines have been dispatched to contain the blaze, as well as two helicopters and several air tankers.

The fire is being driven by low relative humidity and strong winds, Cal Fire said.