Nielsen visited California and toured the ravaged areas in both counties. During an evening press conference, she announced President Donald Trump declared a "major disaster" for the counties after the massive Thomas Fire erupted nearly a month ago.
The brush fire, which started on Dec. 4, eventually became the largest wildfire in California's modern history, according to Cal Fire. It charred nearly 282,000 acres, destroyed almost 1,100 structures and costs just under $300 million.
The state, eligible local governments and certain nonprofits will have access to the funds and help provided by the federal government.