(NEXSTAR) – A woman was airlifted to a hospital with “significant injuries” after she was gored by a bison at Yellowstone National Park, officials said Monday.

The 47-year-old woman from Phoenix was walking with another person in a field near the Lake Lodge Cabins on Monday morning, a news release from the park explained. The pair told officials they saw two bison and turned to walk away from the animals.

Unfortunately, one of the bison charged and gored the woman. She suffered “significant injuries to her chest and abdomen,” according to officials, and was airlifted to an Idaho hospital.

Yellowstone rangers say they haven’t yet determined how close the woman and her companion were to the bison when it charged, and the incident remains under investigation. Additional details weren’t immediately available.

The park warns that between mid-July and mid-August, bison are in mating season and “can become agitated more quickly.”

“Bison are unpredictable and can run three times faster than humans,” rangers said.

The National Park Service reminds that park regulations require visitors to remain more than 25 yards from large animals like bison, elk, sheep, moose, and deer, and at least 100 yards from bears and wolves. Violating those regulations could result in fines, or more seriously, injury and death.

This is the first reported bison goring of 2023, according to Yellowstone rangers. The last reported incident happened in June 2022 when a 34-year-old Colorado Springs man was gored and suffered an arm injury. Rangers said the man was walking with his family on a boardwalk near Giant Geyser at Old Faithful when the bison charged them. The family did not leave the area, and the bison proceeded to charge and gore the man.

Just days later, a 71-year-old woman was gored by a bison she and her daughter “inadvertently approached” in Yellowstone. Months earlier, a 25-year-old woman was tossed 10 feet into the air by a bison she approached while walking near Old Faithful.

Yellowstone officials note that if you see a visitor in person or online doing something that “might hurt them, others, or the park” to report it to a ranger or, if you’re in the park, dial 911.