Three mountaineers from Latvia have died following an accident at the summit of Denali, the highest peak in North America, according to German news agency dpa.
Another member of the seven-person expedition was reported to be in critical condition and has been taken to hospital, the Latvian Mountaineering Federation said.
The group was described as experienced and highly skilled climbers.
Denali, also known as Mount McKinley, stands at nearly 6,200 metres in Alaska, United States.
Denali National Park officials said park rangers received an emergency call on Thursday night reporting that four climbers had fallen while ascending near Denali Pass at an altitude of more than 5,500 metres.
The remaining three members of the group initially attempted to assist the injured climbers before returning to a base camp located at around 5,100 metres.
