Los Angeles, California (CNN) -- Hundreds of fire personnel appeared to be making progress against wildfires ripping across Kern County, California.
The southern California community was hit this week by two wildfires 60 miles apart: the Bull Fire, southeast of the town of Tehachapi, and the West Fire, north of Tehachapi in the Sequoia National Forest.
Fire and forestry officials reported little fire activity in the Bull Fire overnight, though the blaze still was burning in grass and brush on both sides of the Kern River. The Bull Fire is 12 percent contained, and has burned more than 16,000 acres.
Thursday, crews will continue to mop up the fire line on the southern edge of the fire to make sure no hot spots remain. And crews will continue the construction of a fire line along the western and eastern flanks, as well as the northern perimeter, to stop the fire's spread. Helicopters and air tankers will be on hand to support crews working on the ground.
The Bull Fire hasn't prompted evacuations. Eight homes and six outbuildings have been destroyed in the Bull Fire.
Fire officials revised the number of structures destroyed by the West Fire to 25, down from 30 to 40, according to CNN affiliate KTLA. Most were homes.
The West Fire has burned more than 1,400 acres. It was 25 percent contained Wednesday night, according to Kern County fire officials. Lower temperatures and calmer winds made firefighting efforts a little easier. The California Department of Forestry and Fire Protection told CNN affiliate KTLA that if the weather continued to cooperate, they expected to have the West Fire fully contained by Friday.
A task force made up of law enforcement personnel from the U.S. Forest Service, Bureau of Land Management, Kern County Fire Department, and the Kern County Sheriff's Office was formed to investigate the Bull Fire. The task force, which was following up on multiple tips called in by residents, has set up a tip line for anyone with information pertaining to the start of the Bull Fire: 1-877-FIRE-TIP (1-877-347-3847).
Wednesday, California Gov. Arnold Schwarznegger declared a state of emergency for Kern County.
An evacuation center was set up at the old junior high school in Tehachapi for evacuees and their pets. Animal control was taking large animals, authorities said. Hundreds of people are still evacuated out of the path of the West Fire.
One Kern County evacuee told CNN affiliate KTLA, she was evacuating when the fire exploded nearby propane tanks in quick succession. "It was just terrifying," she said.
Visitors and residents are warned to keep their car and house windows closed, as there is a lot of smoke in the area, said U.S. Bureau of Land Management spokeswoman Michelle Puckett. Puckett said wildfires can be sparked by people using off-road vehicles and lawn equipment during midday. She said that using such equipment during early morning and evening, when temperatures are lower and humidity is higher, can help minimize the risk of starting a fire.
The Sequoia National Forest of 1.2 million acres is one of 19 national forests in California. It takes its name from the giant sequoia, the world's largest tree, which grows in more than 30 groves on the forest's lower slopes.
This is a prime time for tourism in the area, with no vacancies at hotels and bed-and-breakfasts, Puckett said.
Kern County is approximately 130 miles north of Los Angeles.