UPDATE, SUNDAY 10 AM: With Santa Ana winds dying down and firefighters getting a handle on the Saddleridge Fire, evacuation orders have been lifted for most people in the Sylmar, Porter Ranch and other communities in the north San Fernando Valley areas. The first is now reportedly 41% contained, with onshore breezes and elevated humidity aiding the battle.

While the fire’s cause has not been determined, some Sylmar residents reported seeing a fire burning at the base of a transmission tower near Saddle Ridge Road. Investigators are looking at the area as a potential ignition point for the blaze.

The fire has burned an estimated 7,900 acres. At least three people have been reported dead.

UPDATE, SAT. 8:30 AM: Winds that fuel California wildfires appear to be dying down, helping fire fighters get a handle in their overnight battle against the Saddleridge fire. But Red Flag warnings are still in effect in Los Angeles County through the late afternoon, as dry conditions continue. Fire officials say 13 homes have been destroyed, with 18 damaged by the Saddleridge fire, and mandatory evacuations are still in effect.

Power has now been restored to 2 million customers in Northern California, who lost electricity on Wednesday as a precaution against downed power lines sparking a conflagration, as it did last year.

Six Flags Magic Mountain, which closed yesterday after fires closed surrounding freeways, is open again today. The park’s official Twitter account said it would be operating normally and opening at 10:30 AM through 1:00 AM.

UPDATED, 6:15 PM: A fast-moving wildfire fueled by fierce Santa Ana winds swept into the northern Los Angeles area overnight, destroying homes, forcing mandatory evacuations and sending thousands fleeing.

Mayor Eric Garcetti has declared a state of emergency in the city of L.A. “

Because of the severity of this fire and its capability to escalate, I signed a Declaration of Emergency for the City of Los Angeles about an hour ago,” he said at a late-afternoon press conference. “That’s been received by the county, and our state officials will speak to a state declaration as well.” Garcetti said he has been in touch with Gov. Gavin Newsom since Thursday night to “ensure that we have the resources necessary to knock down these fires and to protect our communities.”

As of early afternoon Friday, all of Los Angeles’ local TV stations were covering the fire live, which fire officials said has burned more than 7,500 acres and is 13% contained. All mandatory evacuations remain in place — the latest being for all of Porter Ranch — as do the red-flag warnings.

Noah Berger/Shutterstock

At a news conference this afternoon from Hansen Dam, David Richardson, Chief Deputy of Emergency Operations for the Los Angeles County Fire Department, said: “It appears there’s a lull in activity, but don’t be fooled: There’s a lot of open fire line, there a lot of potential for continued growth of this fire. … It’s gonna be a number of days.”

U.S. Rep. Brad Sherman was among those evacuated overnight, as were some other local elected officials.

The Saddleridge Fire broke out at about 9 p.m. Thursday in the Sylmar area, jumping the 210 and 5 freeways and exploding, according to the Los Angeles Fire Department. Portions of the 5, 210 and 118 freeways — all major arteries into and out of the northern San Fernando Valley — have been shut down, setting up likely nightmares for rush-hour Friday commuters (see the latest list of closures below).

Six Flags Magic Mountain Closed By Saddleridge Fire, Scraps Plans For Late Opening

Most area schools were closed for the day because of poor air quality, including Cal State Northridge and Moorpark College. High school football scheduled for Friday night in the affected areas have been postponed.

As of 10:30 a.m., the community of Porter Ranch was being hit by the fire, with several homes destroyed. By 11:30 a.m., evacuation orders had been issued for southern Santa Clarita at Sierra Highway, which is closed in both directions. See the latest of open evacuation centers below.

According to LAFD Chief and PIO Ralph Terrazas at a Friday morning news conference, an estimated 25 homes have been damaged and mandatory evacuations have been issued for some 23,900 homes, starting north of the 118 Freeway from Tampa Avenue to the Ventura County line. Some 100,000 people are affected.

One man in his 50s has died of cardiac arrest and one firefighter suffered a minor eye injury, Terrazas said.

He added that the Saddleridge Fire was spreading at a rate of about 800 acres an hour. No cause has been determined. “This is a very dynamic fire,” Terrazas said.

Gov. Gavin Newsom has secured fire-management assistance from FEMA, meaning that 75% of the costs of fighting the fire will be handled by the feds.

More than 1,000 firefighters from multiple agencies are battling the fires. Eight helicopters have been making repeated water drops as crews on the ground attack the flames, and two super scoopers and one Erickson air crane join the fight from the air in the morning as the fire headed west toward the Ventura County.

David Swanson/Shutterstock

Winds of 20-30 mph winds are expected to continue through early afternoon with gusts up to 50 mph in the fire zone, along with very low humidity — 3%-10% — making it a challenge for firefighters who are trying to get the blaze under control. Multiple brush fires have sprung up over the past 24 hours from Riverside to Ventura counties.

“It’s been a battle,” LACFD’s Richardson, said at a morning news conference. “And unfortunately, it’s too familiar. We’ve been here not too long at this very same spot. … There continues to be a firefight out there.”

Fire danger is high throughout Southern California after a very rainy winter and spring that fueled vegetation growth, followed by a typically dry summer and early fall, combined with the destructive Santa Ana winds. Southern California Edison has cut power to nearly 13,000 customers in an effort to limit wildfires, and the utility said power could be cut off to more than 173,000 customers in parts of eight counties.

Residents are encouraged to text the word “Ready” to NotifyLA at 888777, which will provide any updates on evacuation efforts.

Freeway closures as of 6:15 p.m. Friday:

210 eastbound and westbound from the 5 to the 118

14 southbound and northbound from Newhall Avenue to the 5

As of 1:15 p.m., these are the evacuation centers that remain open for people and small animals, followed by a list of centers that are filled to capacity:

Van Nuys Recreation Center

Balboa Recreation Center

Pierce College

Lenark Recreation Center

Hansen Dam Recreation Area & Equestrian Center

West Valley Animal Shelter

Mason Recreation Center

Rancho Santa Susana Community Center

Canoga Discount Birds (birds only)

Fairplex Pomona (horses and other large animals)

At capacity and unable to accept new arrivals:

Granada Hills Recreation Center

Northridge Recreation Center

Sylmar Recreation Center

Patrick Hipes contributed to this report.