A glacial collapse along the Nepal-China border triggered floods and mudslides that have killed at least 353 people and left more than 1,000 missing on both sides, including dozens of American citizens.
Nepal's Tourism Board confirmed Thursday that at least 65 U.S. nationals were among the missing foreign nationals after a wall of ice, rock, and water swept through communities in the Nuwakot and Rasuwa districts on Wednesday. The number nearly doubled from the count reported just one day earlier, and rescue teams working by helicopter pulled more than 100 survivors from the flood zone even as bodies turned up 62 miles downstream.
Nepal Police put the confirmed death toll at 353 with 826 people still missing on the Nepali side alone. Across the border in Tibet, Chinese state broadcaster CCTV reported 558 people missing, 260 of them foreigners, with at least three confirmed dead as of Thursday morning. Combined, more than 1,300 people remain unaccounted for across one of the most remote stretches of the Himalayas.
The U.S. Geological Survey initially flagged the event Wednesday morning as a magnitude 4.4 earthquake roughly 41 miles north of Kathmandu. Hours later, USGS revised its assessment: the seismic signal came from a magnitude 5.2 glacial collapse, not a tectonic event. The agency based its updated determination on data from nearby seismic stations, long-period seismic waves, and satellite imagery, and stated flatly that no earthquake had occurred.
Saswata Sanyal, a disaster risk reduction specialist at the International Centre for Integrated Mountain Development in Kathmandu, explained the mechanics. An ice rock avalanche from a glacier on the Nepal side broke loose, blocked the Lhende Khola River, a tributary of the Bhotekoshi, and then released a sudden surge downstream.
Sanyal told CBS News:
"The Lhende Khola has flooded twice in 14 months, this time triggered by an ice rock avalanche from a glacier on the Nepal side that blocked the river and released a sudden surge downstream."
Climate experts at ICIMOD said hydrological observations confirmed the speed and scale of the flood wave. At one monitoring point on the Trishuli River, water levels rose as much as 27 feet in half an hour. Villages, roads, bridges, and power plants were destroyed. Drone footage from Wednesday showed buildings buried and roads ripped apart.
Shoyam Rajbhandari, a resident who reached the Dhunge bazaar area shortly before the surge hit, described the destruction in real time:
"When I reached Dhunge bazaar, in half an hour, the flood came and damaged all the market. People were preparing to go to office then. How many people are missing or dead, we don't know."
Nepal's National Emergency Operation Center broke down the missing on the Nepali side: 113 were tourists, 85 were security personnel, army and police, and 161 were local residents. The mix of casualties underscores how many people were in the area when the surge arrived, from trekkers and pilgrims to soldiers and families going about their morning.
Bodies recovered in Chitwan district, roughly 62 miles downstream from the worst-hit areas, gave rescuers a grim measure of how far the floodwaters carried victims.
Hikmat Singh Ayer, CEO and senior director of the Nepal Tourism Board, told CBS News on Thursday that at least 65 Americans were among the missing foreign nationals. A subsequent update from the Tourism Board said 27 foreign nationals had been rescued from the Rasuwa flood zone, including two U.S. nationals, a man and a woman in their 50s.
A U.S. State Department spokesperson told CBS News Thursday that the agency was aware of about 90 Americans who may have been impacted by the floods. The spokesperson said the department was not yet aware of any American deaths and was continuing to closely track the situation. The State Department also said it was sending an adviser to the region.
The U.S. Embassy in Nepal posted a series of statements on social media, expressing "heartfelt condolences to the families and loved ones of those who lost their lives in the devastating floods" and said it was "working to account for U.S. citizens who may have been affected." The embassy urged Americans in the region to contact their families, hotels, guides, and tour companies.
Secretary of State Marco Rubio posted on X Wednesday that the State Department "stands ready to support the government of Nepal with needed humanitarian assistance." The department announced a $500,000 grant to Catholic Relief Services as part of its initial response.
Brigadier General Raja Ram Basnet, the Nepalese Army's spokesperson, said army helicopters rescued more than 100 people from flood-affected areas on Thursday. At least eight foreign nationals were airlifted to Kathmandu. Army teams also evacuated people trapped inside facilities linked to the Trishuli hydropower project. Private helicopter operators joined the effort alongside military aircraft.
On the Chinese side, conditions near the Gyirong Port land border crossing were severe. CCTV reported that the mudslide left mud more than five feet deep on average, with some road sections buried under more than six feet. All roads to the port were damaged. Communication with the area was cut off. Light rain continued, and Chinese authorities warned that secondary collapses or landslides could follow. A barrier lake, formed when debris dams a waterway, was discovered near the port, adding another hazard.
Chinese authorities deployed large military transport aircraft to send teams into the Tibet region. Indian nationals on pilgrimage to Mount Kailash, a sacred Hindu site in Tibet, were also reported among the missing.
The Dalai Lama issued a statement Thursday, reported by AFP:
"I pray for all those who have lost their lives, and offer my sympathy and heartfelt condolences to the bereaved and to all those affected by this tragedy."
This was not the first time. Similar flash floods struck the same border region in August of last year when a glacial lake in Tibet overflowed due to high temperatures. That event killed nine people and damaged the bridge connecting Nepal and China. The Lhende Khola had now flooded twice in 14 months.
Researchers in Kathmandu reported earlier this year that glacier ice loss rates across the Hindu Kush Himalaya region have doubled since 2000. Sanyal pointed to the pattern, noting the importance of early warnings in what he called "a warming Himalaya."
Communications remain severely disrupted across the disaster zone. Roads are impassable. Rescue teams are working against weather, terrain, and time. Hundreds of families, in Nepal, Tibet, the United States, India, and beyond, still do not know whether their loved ones are alive.
When a river rises 27 feet in half an hour, the only thing that stands between survival and catastrophe is a warning system that works before the water arrives, and right now, this stretch of the Himalayas does not have one.
