One person is dead and another is seriously injured after the pair fell about 1,000 feet while climbing a mountain in Alaska. 

The unnamed climbers were scaling Mt. Johnson, an 8,400-foot peak in Denali National Park, the National Park Service said in a news release. The climbers were ascending a part of the mountain known as "The Escalator," which is on the mountain's southeast face. The route requires navigating a mix of "steep rock, ice and snow" for about 5,000 feet, the NPS said. 

Another climbing party on the route saw the pair fall, the NPS said. The second group alerted the Alaska Regional Communication Center to the incident at about 10:45 p.m. on Thursday night. The second group then descended to the accident victims. 

The second group confirmed that one person had died in the fall. The second had sustained "serious traumatic injuries." The second group dug a snow cave and attended to that climber's injuries throughout the night until Denali National Park's high-altitude rescue helicopter pilot and two mountaineering rangers were launched Friday morning. 

A rescue operation ensued, with a ranger taken to the climbers. The ranger and injured climber were brought to a flat glacier staging area and loaded onto the helicopter. The injured climber was transferred to an air ambulance and taken for further care. The NPS did not specify the climber's injuries, where they were treated, or what their current condition was.

Officials attempted to recover the body of the dead climber on Friday, but were stalled by "deteriorating weather conditions." Another attempt will be made "when weather conditions allow," the NPS said. 

The deceased climber will be identified when family members are notified, the NPS said. 

In:
• Denali
• Alaska