SACRAMENTO, Calif. — Fire officials say firefighters have gained ground against a Northern California wildfire that killed at least 79 people.

The California Department of Forestry and Fire Protection said Tuesday that the fire is now 70 percent contained. That's up from 66 percent Monday morning. The blaze's size remained at 236 square miles.

The gains come ahead of rain forecast for the region starting Wednesday that was expected to last through the Thanksgiving weekend. The National Weather Service issued a flash flood watch for wildfire-scarred areas. It said newly burned areas in and around Paradise are prone to downhill ash and debris flows.

Officials were concerned rain could complicate the efforts of crews searching for human remains by washing away signs of the dead or turning the dusty debris into a thick paste.

Meanwhile, dozens of people who lost their homes in the blaze remained at a makeshift camp next to a Walmart in the city of Chico days after they were asked to go to a shelter.

Evacuees camping on the sprawling parking lot were asked to leave before rain arrives Wednesday, but some said they preferred to stay in tents because shelters would not accept them with their pets.

The blaze that started Nov. 8 leveled Paradise, destroying 310 apartment buildings and more than 12,500 homes. The death toll nearly two weeks after the inferno stood at 79, with about 700 people unaccounted for.

Authorities were using a rapid DNA test that produces results in just two hours to help identify human remains. 

Southern California

In Southern California, victims of a destructive wildfire sued Southern California Edison, alleging the utility was negligent in failing to shut off power before the blaze started.

Plaintiffs' attorneys said Tuesday that nearly 20 people were part of the class-action lawsuit filed last week.

Edison said in a statement that it can't comment on litigation related to wildfires.

The cause of the so-called Woolsey Fire remains under investigation. The fire has destroyed at least 1,500 structures since erupting Nov. 8. Full containment is expected this week.

Preventing fires

Meanwhile, a top Trump administration official is accusing "radical environmentalists" of blocking thinning and grazing in forests that he says could prevent wildfires.

Interior Secretary Ryan Zinke reiterated the administration's blame of environmental policies in a call with reporters on Tuesday.

He cites "lawsuit after lawsuit" by "the radical environmental groups that would rather burn down the entire forest than cut a single tree."

Many wildfire experts and California's Democratic leaders counter the Trump administration's arguments, saying most of California's deadly recent fires are not in forests, and that thinning trees would not have affected those blazes.