A woman who was found dead inside her Northern California home last year was the state's first documented fatal black bear attack on a human, wildlife officials said.

Patrice Miller, 71, a resident of Downieville, a community about 100 miles northeast of Sacramento, was discovered deceased in her home on Nov. 8, 2023, according to the Sierra County Sheriff’s Office. Deputies were conducting a welfare check after Miller had not been seen or heard from in several days.

The California Department of Fish and Wildlife told USA TODAY that a black bear attacked and killed Miller. The animal was later trapped and euthanized.

"This incident is the first known, documented fatal attack by a black bear in California history," spokesman Peter Tira said.

Authorities initially thought the bear entered Miller's home after she died. But the department said Thursday that a coroner determined the bear caused her death.

The day Miller's body was discovered, deputies "immediately saw evidence of bear intrusion," including a broken door and bear scat on the porch, Sierra County Sheriff Mike Fisher told KCRA-TV on Wednesday.

"It appeared that the bear had probably been there several days and had been feeding on the remains," Fisher told KCRA.

Fisher said an autopsy revealed Miller had been killed when the bear swiped or bit her in the neck area.

The autopsy's results were first reported by The Mountain Messenger in May.

'Historic' attack serves as reminder of wildlife's danger

Tira said the fatal black bear attack is a historic incident.

"It’s historic, and a stark, sad reminder that black bears are big, strong powerful wild animals that need to be respected," he said.

One aspect of the attack that's particularly concerning is that the bear accessed the inside of Miller's home in the first place. When that happens, Tira said, the bear's behavior becomes much more dangerous, quickly.

As soon as a bear gets comfortable and loses its fear of humans, he said, it will "become bolder and more brazen" in its attempt to get food.

"Black bears aren’t typically dangerous, but when they gain access – intentionally or unintentionally – to human-sourced food or garbage their behavior changes," Tira said.

Black bear attacks still rare

Black bears are the only wild bears that live in California, according to the state Department of Fish and Wildlife. The agency has estimated that between 25,000 and 35,000 black bears occupy more than 50,000 square miles in the state.

While a black bear weighs about 300 pounds on average, the animal can weigh up to 500 pounds. Black bears are strong swimmers and tree climbers and can run up to 35 mph.

Although black bears often avoid confrontation with humans, interactions in recent years have drawn national attention. Bears, for example, have broken into people's homes or trash cans, typically searching for food.

"Bears that are accustomed to people can become too bold and lose their fear of humans," according to the California Department of Fish and Wildlife.

The agency has noted that black bear encounters that cause human injury are rare in California, but added that the animal can be "unpredictable."

"Most black bear 'attacks' are defensive actions if the animal is protecting cubs, becomes startled or scared," the agency said on its website. "In some cases, a food-conditioned, or habituated bear may become too bold and act aggressively towards people."

The agency recommends that people in bear territory should be aware of their surroundings and watch for signs of bears in the area. If encountering a bear, the agency advises people to avoid eye contact, and back away slowly while also making noises and themselves look bigger.

"If a black bear makes contact − fight back!" the agency said.