Updated at 10:20 p.m. ET.:
Authorities in San Diego County ordered additional evacuations Thursday afternoon as a wildfire began "making an extreme run," as one state fire captain said.
The Associated Press is reporting that a badly burned body found in a transient camp in Carlsbad is the first reported fatality from the wildfires. The city says it had no information about person who died.
The wildfire that started Wednesday afternoon near Cal State University San Marcos was driven by wind in several directions Thursday, heading north, east and west.
An additional 13,000 evacuation notices were issued Thursday afternoon as the fire grew to 1,000 acres.
"The fire is creating its own environment and sucking oxygen in," said Dave Allen of the California Department of Forestry and Fire Protection, according to member station KPBS.
The blaze, known as the Cocos fire, is one of nine different fires that have been plaguing San Diego County over the past three days.
Three homes had already been destroyed by the blaze before it shifted course and thousands had evacuated. Several more homes burned as the fire spread Thursday afternoon.
"As the fires in the north county and the east county have died down, San Marcos has become the focus of our resources," San Diego County Sheriff Bill Gore said at a news conference Thursday morning.
Temperatures remain well above normal and were expected to top 100 degrees in inland areas Thursday, before a cooling trend starts this weekend.
"Fires love low humidity," Alex Tardy, a meteorologist with the National Weather Service, told KPBS.
Despite the difficulties presented by multiple fires, area officials praised the cooperation they are seeing across jurisdictional lines, including the use of a dozen Marine helicopters and the promise of federal aid.
California Gov. Jerry Brown, a Democrat, declared a state of emergency in San Diego County on Wednesday.
"You're seeing the highest level of efficiency and cooperation," said Dianne Jacob, president of the San Diego County Board of Supervisors. "It's a big deal."
Fires have burned thousands of acres across the county. NASA's Goddard Space Flight Center tweeted a photo showing smoke from the fires is visible from space.
The Tomahawk fire at Camp Pendleton has burned 6,000 acres and was considered 20 percent contained as of Thursday morning.
At a dawn news conference Thursday, Carlsbad Mayor Matt Hall announced that four single-family homes and an 18-unit dwelling had been destroyed by the 400-acre fire in his coastal city, along with two commercial properties.
The Poinsettia fire in Carlsbad was considered 60 percent contained as of Thursday afternoon.
With several of the fires, investigators are looking into the possibility of arson.
"'Fire bugs' is the term being used inside the fire agencies," reports KGTV, the local ABC affiliate. "Sources say the fires started in a way that were not normal — there were no sparks from a lawnmower or car engine, no thrown cigarettes and no cars involved."
Officials warned that this is only the beginning of what promises to be a very long fire season in the drought-stricken state.
For more on fire conditions in California and across most of the U.S., check out NPR's Fire Forecast app, which is updated daily. The interactive should take you right to San Diego County, but you can change the location by entering a new "ZIP code, city, etc."