The Saddleridge Fire is just 19 percent contained, but tens of thousands of people were allowed to return home Saturday.

Tens of thousands of evacuated Porter Ranch and Granada Hills residents are now able to return home even though the massive Saddleridge fire continues to rage, destroying dozens of homes and blackening more than 7,542 acres. Authorities lifted evacuation orders Saturday as the blaze reached 19 percent containment.

Gov. Gavin Newsom had declared a state of emergency for Los Angeles county (and Riverside county) where at least 31 homes have been damaged by the blaze and 100,000 people were forced from their homes since Thursday.  The declarations free up local and state resources to aid in the firefighting effort.Police spent the night escorting residents back into their homes for five minute intervals, allowing them to collect the vital belongings they were forced to leave behind due to the fast-moving fire.

The Saddleridge Fire has created dangerously unhealthy air quality over a huge chunk of the Southland, which continues to pose concerns.

Officials said the blaze was 19% contained as of Saturday morning — which remains the latest update — and was burning in the areas of Sylmar, Granada Hills and Porter Ranch.

Ralph Terrazas, chief of the Los Angeles Fire Department, said 13 structures were destroyed, while the rest suffered varying degrees of damage.

Please keep the family of Aiman Eisabbah in your thoughts and prayers.  Aiman suffered a fatal heart attack while hosing down his Porter Ranch home trying to protect it from the fire. Terrazas said Aiman was actually speaking to firefighters when he went into cardiac arrest, and he died at a hospital.

One firefighter suffered a minor eye injury, according to the LAFD.

Humidity levels remained in the single digits Saturday, prompting an extension of a red flag warning until 6 p.m. Santa Ana wind levels were gusting lighter at 20 to 30 mph and could reach as high as 40 mph in the afternoon, according to the National Weather Service.

An unhealthful smoke advisory was issued by the South Coast Air Quality Management District through at least Sunday morning for the entire San Fernando Valley, areas west of central Los Angeles, and coastal areas west of the 110 Freeway. People who can smell smoke or see ash are advised to remain indoors with windows and doors closed, and avoid vigorous physical activity. Officials said that winds were expected to push the smoke east into Pasadena.

The massive fire had prompted a mandatory evacuation order for all residents of Porter Ranch north of the Ronald Reagan (118) Freeway from Reseda Boulevard to DeSoto Avenue, residents of Granada Hills from Balboa Boulevard and north of Sesnon Boulevard to the Ventura County border, and the Oakridge Estates community north of the Foothill Freeway in Sylmar. In all, it affected roughly 23,000 homes — equating to about 100,000 people, authorities said.

The southbound Golden State Freeway truck route, the southbound Antelope Valley Freeway to the southbound Golden State Freeway truck route and the northbound Golden State Freeway to the northbound Antelope Valley Freeway truck route all remained closed.

Roughly 1,000 firefighters from LAFD, Los Angeles County Fire Department and Angeles National Forest were on the ground battling the flames, aided by water-dropping helicopters and fixed-wing aircraft dropping fire retardant.

Los Angeles Mayor Eric Garcetti, who cut short a trip to Copenhagen, Denmark, due to the fire, and county Board of Supervisors chair Janice Hahn both signed local emergency declarations.

The USPS announced that mail delivery would be attempted Saturday “in all accessible areas.” The post office at 19300 Rinaldi St. in Porter Ranch reopened for business from 10 a.m. to 3 p.m. Saturday.

There was no immediate word on what sparked the blaze. Terrazas noted that city officials had been working with the Los Angeles Homeless Services Authority to clear homeless people out of fire-prone areas during the red-flag conditions that began Thursday, but he said he did not know whether there were any encampments near the flashpoint of the blaze.

Various media reports cited a witness claiming the first flames erupted at the base of a Southern California Edison transmission tower along Saddle Ridge Road. Terrazas said he was aware of the reports “of a witness seeing fire fall from a transmission tower,” but there still had not been any determination of what caused the fire.

The fire was first reported just after 9 p.m. Thursday off the westbound Foothill (210) Freeway near Yarnell Street and Saddle Ridge Road in Sylmar, and quickly spread due to wind-blown embers that jumped the Golden State (5) Freeway about 11:20 p.m., spreading the flames into Granada Hills and Porter Ranch.