A Pennsylvania woman drowned Sunday after she was swept over a series of waterfalls and pinned underwater by a log at Glacier National Park in Montana.

According to witnesses, Gillian Tones, 26, slipped on wet rocks and fell into Virginia Creek between St. Mary Falls and Virginia Falls in the afternoon, the National Park Service said Tuesday in a news release.

“Tones was quickly swept up by the cold, fast moving water and went over a series of smaller waterfalls, then was pinned underwater by a log for several minutes until heroic efforts by other park visitors led to pulling her from the river,” the National Park Service said.

The park’s dispatch received multiple 911 calls regarding the incident at about 5:20 p.m. and rangers arrived on scene around 25 minutes later.

Bystanders who pulled Tones from the water attempted to resuscitate her until park rangers and emergency personnel arrived on scene. The 26-year-old did not regain consciousness and resuscitation efforts were stopped at around 7 p.m.

Her body was taken to the medical examiner in Missoula, Montana, for an autopsy.

“The park extends their deepest condolences to family and friends of Tones and asks that the public respect their privacy,” the National Park Service said.

This article was originally published on NBCNews.com