Updated

SODA SPRINGS — A brother and sister from Arizona fell through the ice Sunday afternoon at Alexander Reservoir near Soda Springs while attempting to fish, and despite a harrowing rescue effort by emergency personnel, the woman did not survive.

The Caribou County Sheriff’s Office Emergency Communication Center received the call at about 2:52 p.m. reporting that two people had broken through the ice approximately 200 feet from the northern shoreline of the reservoir, about two miles west of Soda Springs.

Sheriff’s deputies and emergency personnel arrived and immediately crossed the unstable ice — at significant risk to themselves — to reach the victims. They pulled the first victim, a 34-year-old man, from the frigid water and got him back to shore across ice that threatened to give way beneath them. He was treated by EMTs and transported by Caribou County EMS to Caribou Medical Center in Soda Springs. He is expected to make a full recovery, authorities said.

The second victim, the man’s 27-year-old sister, had gone underwater during the effort to rescue her brother. Members of the Sheriff’s Office dive team responded and a dive-certified deputy entered the ice opening to search for her. He located her beneath the surface and brought her to shore, where EMTs immediately began treatment. She was transported via ambulance to Caribou Medical Center, where she was pronounced dead.

The brother and sister, whose names haven’t been released, had walked out onto the ice to fish. The ice where they fell through was only four inches thick, the Sheriff’s Office said.

“The Caribou County Sheriff’s Office offers our condolences to the friends and family of the victims of this terrible accident,” the Sheriff’s Office said in a news release following the incident.

The Get Outside and Live Idaho local nonprofit had previously scheduled a polar plunge event on Saturday but announced on Facebook Monday morning that the event has been canceled out of respect following the tragic incident.

Multiple agencies responded including the Caribou County Sheriff’s Office, Caribou County Search and Rescue and dive team, Caribou County EMS, the Bear Lake County Sheriff’s Office dive team and an air rescue helicopter from Burley. Caribou Medical Center also provided critical care.