Three climbers attempting to reach the summit of a mountain in the state of Washington were killed after one of the climbers in the group triggered an avalanche, authorities say.

A group of six climbers were caught in an avalanche Sunday while ascending the 8,705-foot Colchuck Peak in the Cascade Mountains north of Seattle, ABC News reported. Three members of the group were killed when they were swept 500 feet down the mountain, succumbing to injuries they received in the fall, the Chelan County Sheriff’s Office stated in a release.

A fourth member of the group, who also slid down the mountain, survived and made his way back to the base camp to join the two other surviving members of the group, despite his injuries, the release said. (RELATED: Brothers Go On Heli Skiing Trip In Canada, Die From Avalanche)

Three climbers who were attempting to reach the 8,705-foot peak of a mountain in Washington State over the weekend were killed after a climber in their group triggered an avalanche, the authorities said. https://t.co/LGn5n9wyV3

— The New York Times (@nytimes) February 22, 2023

Rich Magnussen, the emergency management program specialist for the Chelan County Sheriff’s Office, told The New York Times (NYT) the climbers were not aware of the avalanche forecast projected for Sunday morning as the made their ascent. “It’s real extreme conditions up there,” Magnussen stated. “So when you get snow down here in the valley, you can times it by 10 up there.”

Magnussen revealed that the two climbers not caught up in the slide were situated behind a rock when the avalanche occurred, telling the NYT they were “very lucky.” The survivor of the fall, a 56-year-old man from New York, reportedly told officials two of the climbers died instantly while the third appeared to be “hanging on”. After performing life saving measures, however, three more slides came down upon them. “What they’re telling us is after those other slides, it looks like it may have covered the three up,” Magnussen stated.

Poor weather conditions prevented officials from recovering the bodies of the three deceased who are still on the side of the mountain, according to the NYT. The Chelan County Sheriff’s office told the outlet it hopes to send a recovery operation on Thursday if weather conditions allow.