Firefighters are tackling a new brush fire — dubbed the Sepulveda Fire — near Interstate 405 and Sepulveda Blvd in Los Angeles. The fire sparked hours after fire crews started to achieve some containment on the Hughes Fire, which spread rapidly Wednesday afternoon in a Los Angeles County suburb.

An evacuation warning for the brush fire was issued for some residents in Sherman Oaks around 11:40 p.m. Wednesday — the warning has since been lifted, but smoke could be seen in the area near locations including campuses for UCLA and for Mount Saint Mary’s University-Los Angeles. Also nearby are the Getty Center, whose spokesperson told the Los Angeles Times it implemented fire protection protocols, as well as pricey real estate valued in the tens of millions of dollars, according to local listings.

The Sepulveda Fire has burned roughly 40 acres, according to the Los Angeles Fire Department. Firefighters will remain on scene throughout the morning and work to eliminate any remaining hot spots.

“Air support and other aggressive actions have been deployed to fight a new fire just east of the 405,” Los Angeles Mayor Karen Bass said on social media.

Fire engines lined the roads below the blaze as water-dropping aircraft operated overhead, CNN affiliate KCAL/KCBS reported.

The fire threat remains critical in Southern California, where thousands of residents were under evacuation orders Wednesday as fire crews battled the out-of-control Hughes Fire near Castaic.

The fire – impacting both Los Angeles and Ventura counties – had burned more than 10,000 acres and is 14% contained as of Thursday morning, according to the California Department of Forestry and Fire Protection. No structures have been reported damaged or destroyed, Los Angeles County Fire Department Chief Anthony Marrone said at a Wednesday evening news conference.

The unincorporated community of Castaic is about 15 miles northwest of the city of Santa Clarita and borders the Angeles National Forest. Approximately 31,000 residents in the area are under evacuation orders, while 23,000 are under evacuation warnings, according to Los Angeles County Sheriff Robert Luna.

“We have over 4,000 firefighting personnel assigned to the incident,” Marrone said, noting the “robust” ground and air response to the fire. “The situation remains dynamic and the fire remains a difficult fire to contain, although we are getting the upper hand,” Marrone added.

A firefighter sets out fire hoses to fight the Hughes Fire on Wednesday. – Ethan Swope/AP

The Hughes Fire started just before 11 a.m. Wednesday near Castaic Lake, north of where fire crews are working to fully contain the Palisades and Eaton Fires that have scorched more than 40,000 acres and left at least 28 dead since they began January 7.

The fire is “a completely different beast” to the Palisades and Eaton Fires, LA County Fire Capt. Sheila Kelliher told CNN’s Laura Coates Thursday. Two weeks ago, firefighters faced extreme challenges as powerful winds grounded aerial support.

Current conditions are more favorable, with calmer winds allowing the fire department’s helicopters to carry out water drops throughout the night, Kelliher said.

When asked about potential water supply issues, Kelliher said that today’s crews are fortunate to have direct access to Castaic Lake and other nearby reservoirs for their firefighting efforts.

Robert Garcia, Angeles National Forest fire chief, said Wednesday, “The conditions that we’re under aren’t as severe as what we’ve been facing over the last week or two, but what you saw (Wednesday) is indicative of the conditions that we’re in, in terms of the vegetation.”

The area where the fire is burning is known for its dry, grassy hills, fire officials added, making the fire conditions there “critical,” according to Garcia.

“Certainly, we are not out of the woods yet,” said Cal Fire Chief Joe Tyler on Wednesday. Evacuees should follow the directions of local law enforcement and first responders as they are asked to evacuate the area, Tyler noted.

The National Weather Service extended a red flag warning through Friday morning for most of Los Angeles and Ventura counties as Santa Ana winds continue to move through the area, Marrone said.

The winds are expected to intensify across Southern California, peaking late Wednesday into early Thursday. While forecasts indicate a decrease in strength by Thursday afternoon, conditions will still be strong enough to sustain fire weather concerns through Friday morning.

“Dangerous fire weather conditions will persist through Friday as fuels remain extremely dry and ready to burn, with Thursday the period of greatest concern. Any fire that starts can grow fast and out of control,” the National Weather Service in Los Angeles said.

Schools and jail evacuated as Hughes Fire poses risks

A county jail in Castaic has been partially evacuated, according to a spokesperson for the Los Angeles County Sheriff’s Department. The jail is just south of the fire area and can hold as many as 4,295 inmates.

Approximately 470 inmates were evacuated from one of the three facilities on the campus and moved to another part of the detention center, Luna said, adding that the other two facilities are “structured much better” than the one that was evacuated.

“We do have a plan in place … to evacuate the rest of the inmates on the entire facility if we absolutely had to,” Luna said, without providing details.

Meanwhile, all students who attend Castaic Middle School and Castaic High School were evacuated Wednesday to a Ralph’s supermarket parking lot, according to the California Highway Patrol. Students from North Lake Elementary were evacuated to the Castaic Sports Complex, the agency said on X.

The Valencia and Canyon Country campuses of College of the Canyons have been closed as a “precautionary measure” because of the Hughes Fire, the college said on its website.

Smoke was visible as far south as the city of Oxnard, about 50 miles southwest of Castaic in Ventura County, city officials said on social media Wednesday.

The fire will likely spread toward the south and west, away from where it started, according to data and forecast models from thermal intelligence company Orora Technologies. Castaic is in considerable danger of being affected by spreading flames, the models show.

A vehicle rides past a hillside engulfed in flames caused by the Hughes Fire on Wednesday. – Ethan Swope/AP

Satellite data used by Orora Technologies first detected a hotspot just north of Castaic Lake at 10:45 a.m. Officials with Cal Fire said they first detected a fire at 10:53 a.m.

The area where the fire started and is currently burning is largely shrub and grassland, with some limited forested areas, additional data from Orora Technologies shows.

Thick brush in the area is serving as fuel for the rapid fire spread, according to Angeles National Forest spokesperson Dana Dierkes.

“We’re in fairly steep conditions” and it’s “incredibly dry,” Dierkes told CNN affiliate KCAL on Wednesday. “There are homes in the general vicinity and in the immediate area.”

Fire officials previously told KCAL at least 10 firefighting aircraft had been requested for the aerial attack.

The entirety of Angeles National Forest is closed to the general public through January 24, according to the US Forest Service.

This is a developing story and will be updated.

CNN’s Josh Campbell, Artemis Moshtaghian and Isaac Yee contributed to this report.

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