An avalanche that crashed through a camp on Nepal’s Mount Yalung Ri on Monday has killed at least three people, with four foreign climbers still missing, officials said.

At least 16 people were climbing the 5,630-meter (18,471–foot) mountain when the avalanche struck base camp around 10:30 a.m. local time, Gyan Kumar Mahato, the Deputy Superintendent of Police in Nepal’s Dolakha district said.

Among the three confirmed dead is a French national and two Nepali guides, Mahato said. Four people were rescued — two French and two Nepali nationals — and five Nepalis were able to make their own way back to base camp, located at 4,900 meters (16,070 feet).

The nationalities and the identities of the foreign climbers still missing have not yet been confirmed, but Mahato said the group included climbers from France, Canada and Italy.

Authorities had previously said seven people had died on the mountain before revising down the figure on Tuesday.

Weather has been deteriorating since last week in Nepal, with snowstorms reported on the mountains, the Associated Press reported.

Search and rescue teams launched an hours-long operation to reach the climbers but the weather conditions, high altitude and difficult terrain complicated their efforts. Rescuers were reaching the site on foot after a rescue helicopter attempted to reach the site, but bad weather forced it to turn back, AP reported.

“There’s a problem of oxygen also,” Mahato told CNN. “Only trained people who live in hilly, mountain area can conduct rescue operations. That’s why we are coordinating with local climbers and guides. The weather is a challenge too, it’s constantly changing.”

Four of the group were rescued on Tuesday morning and transferred to hospital, according to Mahato. The extent of their injuries is unclear.

The five who trekked back to base camp were Nepali porters and guides, Mahato said.

Mountaineering expedition companies describe Mount Yalung Ri, located in eastern Nepal’s Rolwaling Valley, as a peak suitable for beginners with no previous experience or for those acclimatizing for higher summits of the Himalayas, which can tower above 8,000 meters.

Nepal is home to eight of the world’s 14 tallest mountains, including Mount Everest.

Spring is the most popular climbing season, when weather is more favorable on those tall peaks. However, hundreds of foreign climbers come to climb smaller peaks during the autumn months between the rainy monsoon months and winter, according to AP.

Mahato said that while the avalanche occurred “suddenly,” authorities had warned climbers in the region about the rain and imminent monsoon.

“But they had started their climb before the monsoon occurred,” he said.

Man-made climate change has made weather patterns less predictable, including in the Himalayas.

Last month hundreds of trekkers had to be rescued from the northern Chinese side of Everest after unusually heavy snow and rainfall pummelled the Himalayas. (CNN)