A snowmobiler died during an avalanche in southern Montana on Saturday, officials said Sunday.
The 33-year-old rider, who was from North Dakota, became trapped under six feet of snow on the southeast face of Sheep Mountain in Gallatin National Forest at approximately 1 p.m., officials said.
He was equipped with an inflatable airbag but was unable to deploy it, said Eric Knoff, a forecaster with the forest's avalanche center.
Two others who were also trapped in the slide escaped "relatively unharmed," Knoff said.
A search and rescue team was dispatched to the mountain just before 2 p.m. (4 p.m. ET), the Park County Sheriff's Office said, and unsuccessfully administered CPR.
The three snowmobilers were part of a five-member group and were "reportedly experienced riders," Park County Undersheriff Clay Herbst said, noting that they had beacons, probes, shovels and backpacks that contained airbags.
The avalanche came amid single-digit temperatures, heavy snowfall, strong winds and unstable terrain, Knoff said.
The likelihood of additional avalanches remained high on Sunday, he said.