Brown described the scene as a "war zone," saying, "This is so devastating that I don't really have the words to describe it."
Brown said President Donald Trump, with whom he has often clashed, called him on Wednesday to offer his full support.
"We're in a different kind of world, we know that," he said. "We're in for very difficult times. It'll never be the same. But I can assure you that everyone in California is going to do their best."
Zinke, meanwhile, called the devastation the worst wildfire damage that he had ever seen, calling for new policies and plans to avert a repeat.
"This is unacceptable year after year after year," he said.
The residents who were lucky to escape the massive fire are now also having to deal with a highly contagious virus outbreak at one of the evacuation shelters.
Butte County public health spokeswoman Lisa Almaguer said lab tests confirmed the presence of norovirus at the shelter in Chico, 15 miles west of fire-ravaged Paradise. Almaguer said people who are sick have been taken to a separate location at the shelter and separated from everyone else.
"They have separate restroom facilities and they are being cared for by public health nurses," she said.
Almaguer said there are 179 evacuees at the shelter and 21 are currently ill.
Officials haven't yet determined the cause of the fire, but Pacific Gas & Electric, or PG&E, said in a document filed with the U.S. Securities and Exchange Commission that its equipment may have sparked the blaze. It said it might not have enough insurance to cover the expected cost of the damage.
A spokesperson for PG&E stressed Wednesday that the cause still hadn't officially been pinpointed. But the spokesperson said the company has filed an incident report with the state Public Utilities Commission.
"The information provided in this report is preliminary, and PG&E will fully cooperate with any investigations," the spokesperson said.
PG&E stock closed down by 21.79 percent on Wednesday after a group of Northern California fire lawyers sued in state Superior Court alleging that PG&E failed to properly maintain, repair and replace its equipment and that "its inexcusable behavior contributed to the cause of the 'Camp Fire.'"