The catastrophic floods in Nepal and Tibet that have killed at least 273 people were triggered by a massive glacier collapse and debris flow that registered as a magnitude 5.2 landslide, according to the U.S. Geological Service (USGS).The USGS originally pinpointed the cause of the mudslides as a 4.4 magnitude earthquake but later updated its analysis after observing data from nearby seismic stations, long period seismic waves and satellite imagery. That data suggested that no earthquake had occurred.Climate experts at the Kathmandu-based International Centre for Integrated Mountain Development told The Associated Press that Wednesday’s flash floods were likely triggered by a glacial avalanche.”Hydrological observations indicate the exceptional speed and magnitude of the flood wave,” they said in a statement, adding that at one point, the water levels on the Trishuli River rose by as much as 27 feet in just a half hour.TERRIFYING VIDEO CAPTURES PEOPLE FLEEING INCOMING MUDSLIDE AT NEPAL-CHINA BORDERRescue teams are now searching for the more than 1,300 people who went missing during the floods along the Nepal-China border. Many of them were foreigners and pilgrims.Nepal Police on Thursday began posting lists of Nepali and foreign nationals missing. Several dozen Americans were listed.Dozens of bridges were destroyed and nearly 25 miles of roads were damaged, hampering search and rescue efforts, according to Nepalese officials.The Nepalese army rescued more than 100 people from flood-hit areas by helicopter Thursday morning, according to army spokesperson Brig. Gen. Raja Ram Basnet.Bishal Kumar Bhandari, chairman of the Nepal Red Cross Society, told the AP that they have shifted focus to large-scale relief operations. He said that around 1,200 people were displaced from at least three villages.BABY PULLED FROM VEHICLE TRAPPED IN RAGING FLOODWATERS IN DRAMATIC RESCUE CAUGHT ON VIDEOVideos of the disaster showed raging floodwaters sweeping away cars, engulfing people trying to flee and destroying homes and bridges.Debris was left tangled in tree branches and power lines, vehicles were buried and mud-covered survivors emerged as flooding cut off travel in some areas.The village of Soley in Nuwakot, which has about 25 homes, was almost entirely destroyed, according to Kathmandu-based journalist Nirajan Paudyal, whose parents and other relatives live there. Desperate for news, he traveled to the area Thursday to check on his family.”There is no update till now. I fear there won’t be any update,” Paudyal told the AP.The disaster in Nepal and Tibet underscores a broader threat, as increasingly unstable Himalayan ice poses risks to communities, infrastructure and water supplies across one of the world’s most densely populated regions.The region experienced similar flash flooding in August 2025, when high temperatures caused a glacial lake in Tibet to overflow. The resulting floods killed nine people and damaged critical infrastructure, including a bridge linking Nepal and China.