This attack is the fourth animal-visitor incident of 2018.
Unsurprisingly, it happened after a group of tourists got way too close to one of the huge animals. It happened in the Lower Geyser Basin at the Fountain Paint Pots. According to a National Park Service press release, 59-year-old California resident Kim Hancock suffered a hip injury after she and a group of other tourists got within 15 yards of the bull.
Park officials recommend staying at least 25 yards away from large herbivores like bison and elk.
As the bison crossed the boardwalk, it finally decided enough was enough and charged the group, goring Hancock's leg in the process. She was later transferred to a hospital in Montana, where she was said to be in good condition.
The attacking bison fled the area quickly. Authorities are still investigating.
The first bison attack of the year happened back in early May when one charged a woman near Old Faithful, inflicting minor injuries.
It's been a busy week for park officials. This attack comes right on the heels of two elk attacks in the park, bringing the total number of animal attacks this year to four. Two women were kicked by female elk protecting their young in separate incidents within the same week.
Both of the elk attacks happened in the Mammoth Hot Springs area. Authorities are uncertain if it was the same elk involved in both incidents.