SAN FRANCISCO — Thousands of people forced to flee their homes were allowed to return Thursday after firefighters made progress in their effort to put out massive and deadly wildfires in Northern California. Officials were working on plans to repopulate other evacuated areas.

Cooler weather and higher humidity, along with an influx of equipment and firefighters, continued to help hard-pressed crews fighting some of the largest fires in recent state history, burning in and around the San Francisco Bay Area.

“We’ve had a lot of good success,” said Mark Brunton, a state fire official at a blaze in San Mateo and Santa Cruz counties south of San Francisco, early Thursday.

The fires have claimed seven lives and destroyed 1,800 buildings, according to Cal Fire. In the Santa Cruz area, officials asked anyone with information on the whereabouts of Shane Smith, 21, and Micah Szoke, 37, to call the sheriff’s department. Both men live in evacuation zones and were reported missing.

Solano County, north of San Francisco, began allowing people back home on Thursday. In the heart of wine country, evacuation orders in Napa and Sonoma counties were lifted Wednesday for about 35,000 people who had been told to leave after lightning ignited dozens of blazes last week.

Firefighters and utility workers were clearing areas for returning residents after crews increased containment lines — the creation of fire breaks to prevent wildfires from spreading more — of the massive cluster of fires north of San Francisco to about 33%.

That Fire, the Site of Five of the Deaths, Still Threatened 30,500 Homes and Other Buildings

However, the fire also jumped a highway and threatened homes in neighboring Yolo County near the community of Rumsey, prompting new evacuations Wednesday.

That fire, the site of five of the deaths, still threatened 30,500 homes and other buildings after destroying more than 1,000.

Two of the dead were identified as Douglas Mai, 82, and Leon Bone, 64, both of Vacaville. They died on Aug. 19.

Bone was nearly blind, couldn’t drive and didn’t have a phone, family members told KNTV-TV.

“He was probably taken by complete surprise,” said his cousin, Daniel Bone.

Bone had lived on the property his entire life and refused to move when his parents died, his cousin said.

“He was happy there and that’s the only place he wanted to be,” he said.

To the south, the fire in San Mateo and Santa Cruz counties was 35% contained.

The massive fires — coming months earlier in the season than expected — have already burned more than 2,000 square miles and pushed firefighters to the breaking point, prompting some residents to form crews and fight them on their own.