Two Korean Americans and one Korean national died over the weekend after being swept up in an avalanche on a mountain in Washington state, US, officials said Thursday.

The three climbers, who were part of a six-person group, were attempting to climb a 2,650-meter peak in Washington’s Cascade Mountains on Sunday when the avalanche was “triggered,” the Chelan County Sheriff’s Office said in a press release shared via Twitter.

According to sheriff’s office, the victims were identified as Seong Cho, a 54-year-old male Korean national who had been residing in Connecticut; Jeannie Lee, a 60-year-old female from New York; and Yun Park, a 66-year-old male from New Jersey.

Their bodies were yet to be recovered as of early Thursday due to severe weather conditions at the avalanche site.

In an avalanche “triggered by the lead climber,” initially four climbers were swept some 150 meters down the Northeast Couloir of Colchuck Peak, the authorities explained. The three climbers died from injuries sustained from the fall, while the fourth climber survived due to non-life threatening injuries. No further details about the avalanche were provided.

The fourth climber eventually joined the other survivors from the climbing party. They hiked back to the base camp, where they called for help.

Twenty-two rescuers responded, and the survivors were escorted back to the trailhead. However, the rescuers had not been sent back to the site to recover the bodies as of early Thursday due to safety issues.

“Recovery efforts from this point forward will be based on avalanche and weather conditions as well as overall rescuer safety,” the sheriff’s office said.

A spokesperson for the Consulate General of Korea in Seattle said that the poor weather conditions have been preventing the authorities from dispatching a rescue team via helicopter to the site.