The most destructive wildfires in California’s history have killed at least 31 people and forced tens of thousands more to evacuate as firefighters struggle to gain control amid swirling winds.

The so-called Camp Fire in Northern California and the Woolsey Fire in suburban Los Angeles have destroyed more than 6,700 structures and could cost the state, insurers and homeowners at least $19 billion in damage. The state’s two largest utilities both fell sharply, with Northern California’s PG&E Corp. losing 38 percent, the most intraday in 16 years.

It could take another five days before firefighters put out Woolsey and the rest of the month to extinguish the Camp Fire, the California Department of Forestry and Fire Protection, or Cal Fire, said. Meanwhile, 149,000 people remain evacuated, Mark Ghilarducci, director of California’s Office of Emergency Services., said on Sunday.

The blazes have now spread to more than 196,000 acres and threaten to destroy tens of thousands of structures, according to Cal Fire. About 228 people remain unaccounted for in the vicinity of the northern blaze. Governor Jerry Brown, meanwhile, has formally asked President Donald Trump to release new federal aid in a “major disaster declaration.”

The request for emergency funding to support housing, crisis management and infrastructure recovery efforts came a day after Trump threatened to withhold federal payments to California.

“We’re putting everything we’ve got into the fight against these fires, and this request ensures communities on the front lines get additional federal aid,” Brown said in a statement.

Trading in PG&E was briefly halted after shares dropped for a second day. About 26,000 PG&E customers and 3,286 Edison International customers were without power. Edison fell as much as 25 percent.

The damage north of San Francisco and near Los Angeles could be on par with the type of destruction triggered by Hurricane Michael, which left Florida in disarray earlier this year, said Chuck Watson, a disaster modeler at Enki Research.

“The California fires are as bad as folks think they are,” Watson said, pegging possible damages of about $25 billion. “Insurance for fire is already becoming an issue in California and this won’t help that industry.”

Initially, Trump had threatened to withhold money because of what he called “gross mismanagement of the forests.” His later tweets were more measured, saying that “our hearts are with those fighting the fires.” On Sunday, Trump tweeted again to encourage “proper” management to “stop the devastation constantly going on in California.”

The tweet: “Donald J. Trump @realDonaldTrump More than 4,000 are fighting the Camp and Woolsey Fires in California that have burned over 170,000 acres. Our hearts are with those fighting the fires, the 52,000 who have evacuated, and the families of the 11 who have died. The destruction is catastrophic. God Bless them all.”

Sent via Twitter for iPhone.

As of Nov. 6, all of California is abnormally dry, up from nearly 85 percent the week before, according to the U.S. Drought Monitor in Lincoln, Nebraska. Almost 52 percent of California’s land met drought definitions.

“Statewide we are in a climate change and it is going to be here for the foreseeable future,” said Daryl Osby, chief of the Los Angeles County Fire Department. “Six out of the last seven years, we’ve been in a drought.”

8,000 Firefighters

About 8,000 local, state and federal firefighters are on the scene.

Authorities are investigating electrical equipment as one of several possible causes of the Camp blaze, about 150 miles (240 kilometers) northeast of San Francisco, Cal Fire spokesman Scott McLean said. PG&E is still struggling to cope with losses from last year’s deadly fires that could cost it as much as $17.3 billion in liabilities, according to a JPMorgan Chase & Co. estimate.

Camp Fire has now destroyed more structures than any other wildfire in state history, according to data compiled by Cal Fire. In Southern California, the Woolsey blaze had consumed 83,275 acres in Ventura and Los Angeles counties by early Sunday and was only 10 percent contained.

Hot dry winds fanning flames will persist across Southern California, including Riverside, San Bernardino, Ontario, Fontana and Santa Clarita, according to the U.S. Storm Prediction Center in Norman, Oklahoma. More than 20 million people live in those areas.

Utilities Investigated

A PG&E transmission line in the area went offline 15 minutes before the Camp blaze was first reported, the company said in a regulatory filing. The company also reported finding a damaged transmission tower near where investigators say the fire began.

State investigators linked equipment owned by PG&E to 17 fires that burned in the state last year. Shares of PG&E, which provides electricity in Northern California, fell more than 16 percent on Nov. 9, and were down before the start of regular trading Monday. Edison International, which serves much of the southern part of the state, dropped 12 percent Friday.