A Las Vegas, Nevada woman was seriously injured Sunday after being kicked multiple times by a cow elk behind the Mammoth Hot Springs Hotel inside Yellowstone National Park.

Charlene Triplett, 51, was kicked in her head, torso and back after the elk reared up and kicked her with its front legs, according to a statement from park officials. The elk was protecting a calf, which was bedded down some 20 feet away and was hidden by vehicles.

It was unclear whether Triplett saw the calf or the cow elk before the encounter.

Due to the severity of her injuries, Triplett was flown to the trauma center at Eastern Idaho Regional Medical Center. Park rangers remained in the area to warn others about the elk and calf.

Triplett, an employee at the hotel where the incident occurred, was off-duty when the encounter took place. No citation was issued.

The park urges visitors to use caution around elk, particularly during calving season. People should always remain 25 yards away from the animals.