MALIBU, Calif. — Some of the thousands of people who fled Southern California’s huge wildfire were being allowed to return home, and traffic was flowing Monday on the major highway through the area after a closure of several days.

Repopulation of some neighborhoods and the reopening of U.S. 101 west of Los Angeles began late Sunday, marking positive developments even though forecasts called for continuing critical fire weather conditions.

Mandatory evacuations remained in effect in many other areas, however, including the entire cities of Malibu and Calabasas.

The so-called Woolsey fire grew only slightly on Sunday to just over 133 square miles (344 square kilometers) and by firefighters by nightfall had increased their containment of the blaze to 15 percent.

Authorities planned to release new damage assessments late Monday morning, saying they expected the number of destroyed buildings would be more than the 177 previously reported. The death toll stood at two.

The fire’s cause remains under investigation.

Relief and heartache awaited those starting to return home.

Eager to know the status of his house, 69-year-old Roger Kelly defied evacuation orders Sunday and hiked back into Seminole Springs, his lakeside mobile home community in the Santa Monica Mountains north of Malibu.

His got the thrill of finding his house intact. But some a half-block away were laid to waste, as were dozens more, and virtually everything on the landscape around the community had been turned to ash.

“I just started weeping,” Kelly said. “I just broke down. Your first view of it, man it just gets you.”

The community where Kelly and his wife have lived for 28 years and raised two children was among the hardest hit.

The fire erupted Thursday amid strong Santa Ana winds and spread through communities in western Los Angeles County and southeastern Ventura County.

Santa Ana winds, produced by surface high pressure over the Great Basin squeezing air down through canyons and passes in Southern California’s mountain ranges, are common in autumn and have a long history of fanning destructive wildfires in the region.

A lull Saturday gave firefighters a chance to gain ground but the winds returned Sunday, stoking the fire again.

Los Angeles County Fire Chief Daryl Osby stressed there were numerous hotspots and plenty of fuel that had not yet burned, but at sunset he said there had been huge successes despite “a very challenging day.”

The fire’s cause remained under investigation but Southern California Edison reported to the California Public Utilities Commission that there was an outage on an electrical circuit near where it started as Santa Ana winds blew through the region.

SoCal Edison said the report was submitted out of an abundance of caution although there was no indication from fire officials that its equipment may have been involved. The report said the fire was reported around 2:24 p.m. Thursday, two minutes after the outage.

Ventura County Fire Chief Mark Lorenzen hadn’t heard about the Edison report. “It wouldn’t surprise me” if it turns out that winds caused equipment failure that sparked a fire, he said.

The two dead were severely burned, their bodies discovered in a car on a long residential driveway on a stretch of Mulholland Highway in Malibu, where most of the surrounding structures had burned. Authorities said investigators believed the driver became disoriented and the car was overcome by fire.

The deaths came as authorities in Northern California announced the death toll from a massive wildfire there has reached 29 people, matching the deadliest fire in state history.

Progress was made on the lines of smaller fire to the west in Ventura County, which was 75 percent contained at about 7 square miles (18 square kilometers).

Three firefighters suffered minor injuries on the Woolsey fire, Osby said.

Also injured was a well-known member of the Malibu City Council. Councilman Jefferson “Zuma Jay” Wagner was injured while trying to save his home, which burned down, Councilman Skylar Peak told reporters Sunday.

Peak said Wagner was hospitalized but was expected to recover. Wagner runs Zuma Jay Surfboards, a longtime fixture on Pacific Coast Highway near the landmark Malibu Pier.

The extensive celebrity community within Malibu wasn’t spared. Singer Robin Thicke and actor Gerard Butler and were among those whose homes were damaged or destroyed.

Spot fires continued to occur late Sunday afternoon near the Malibu campus of Pepperdine University, where 3,500 students were sheltering in place. The university said it was closing Malibu campus and its Calabasas campus to the north until Nov. 26 but classes would be remotely administered online and through email.

But fire officials say fire behavior has changed statewide after years of drought and record summer heat that have left vegetation extremely crisp and dry. That change has impacted the ability to move firefighting resources around the state.

“Typically this time of year when we get fires in Southern California we can rely upon our mutual aid partners in Northern California to come assist us because this time of year they’ve already had significant rainfall or even snow,” said Osby, the LA County fire chief.

With the devastation and loss of life in the Northern California fire, “it’s evident from that situation statewide that we’re in climate change and it’s going to be here for the foreseeable future,” he said.

Associated Press writers John Antczak and Andrew Dalton contributed to this report from Los Angeles.

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