A woman severely mauled by three pit bulls while hanging her laundry outside her house in December has died of her injuries, her family said.

Angela Johnson, 54, died Feb. 9, her family said on social media.

"I am sorry to tell you this sad news that my beautiful wife Angela Johnson has passed away this morning," her husband, Reynold Johnson, wrote on Facebook.

The attack was Dec. 15 in the 55000 block of Mitchell Road, according to the Riverside County Fire Department. A responding officer for the Riverside County Department of Animal Services described the victim's injuries as "severe," John Welsh, a department spokesman, said.

She was airlifted to Desert Regional Medical Center following the attack, he said.

Son Tim Platt, writing on a GoFundMe page established after the attack to help with the fundraising, described his mother's condition after she was mauled by her neighbor's three pit bulls, which were euthanized in January:

"The neck bites cut off one of her main arteries to the left side of her brain, causing a severe stroke," he wrote. "She was lifeless when family found her. Her eyes were stuck as wide open as could be ... and that terrified expression stayed on my mom's face until she was airlifted to Desert Regional Hospital."

Johnson was left in a vegetative state after the attack, kept alive by medical equipment.

About two weeks after the attack, Platt wrote that doctors described his mother as brain dead and urged him to allow life support to be turned off. He declined, saying, "If I were her, I wouldn't want anyone giving up on me."

He said doctors told him her quality of life would be severely diminished. "They had to remove half of her skull to make room for the swelling," he wrote on the GoFundMe page. "They say she'll never be able to talk again ... walk ... comprehend anything that's going on around her ... may have issues swallowing ... will stay on life support."

“This is another preventable attack on an innocent person and one we find very upsetting,” Animal Services Director Robert Miller said. “Our hearts go out to her and her family.”

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After the attack, Miller noted that owners of dogs that have "high prey drives" need to have secure yards so they can protect neighboring people and pets.

“It’s imperative that owners of these types of dogs do everything in their power to prevent such horrific attacks,” Miller said.

According to the advocacy website Dogsbite.org, 284 people in the United States were killed by pit bulls from 2005 through 2017.

Neighbor Jesse Leon Miranda, 61, of Anza, who owned the three dogs, was arrested on an outstanding warrant in an unrelated case. As of Tuesday, he had not been charged with the dog attack or Johnson's death, records show.