The National Parks Service said Gillian Tones of North Apollo slipped on a rock and fell into the water above St. Mary Falls on Sunday afternoon, June 23.
Witnesses said Tones was washed over the falls and trapped underwater for "several minutes," rangers said in a release. Bystanders pulled her from the bottom of the falls and rendered CPR before EMTs arrived in a helicopter.
She never regained consciousness and was pronounced dead at 7 p.m., NPS said.
Her remains were taken to the Glacier County Coroner's Office, which turned them over to the medical examiner in Missoula for an autopsy, according to rangers. Her death remains under investigation.
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