Himalayan Flash Flood Kills Nine, Hundreds Missing on Nepal-Tibet Border

A sudden wall of mud and rock crashed into a river along the Nepal-Tibet border on Wednesday, unleashing a flash flood that has killed at least nine people and left hundreds of tourists missing in Nepal's mountainous Rasuwa district.

Security footage from the Chinese side of the border shows people fleeing as the debris flow destroyed buildings and vehicles. Officials in Tibet's Gyirong county fear "major casualties" after the mudslide hit a border land crossing, cutting roads, communications, and power links in the Shigatse region.

Nepal's tourism authority reports that 384 travellers are missing from the affected area, including 105 Indians, 93 Nepalis, three U.S. citizens, and 12 British nationals. South Korea's Yonhap news agency separately reported about eight of its nationals unaccounted for in Nepal.

Nepal's foreign minister, Shisir Khanal, told parliament that an earthquake in the area may have triggered an avalanche and caused the floods. The German Research Centre for Geosciences recorded a 4.4 magnitude quake roughly seven minutes before the time shown on the security footage.

Qianggong Zhang, head of climate and environmental risks at the Kathmandu-based International Centre for Integrated Mountain Development, said an ice-rock avalanche in the Lhende Khola river was the likely trigger, though the cause remains unconfirmed. He warned that a blockage still lodged upstream could cause a second flood.

Rescue helicopters have been unable to land in the affected areas of Syapru Besi and Timure, where the river is flowing above its normal course. District administrator Narendra Pariyar urged residents along the Bhote Koshi river to move to higher ground. "There is devastation everywhere we look," said Tula Bahadur BK, a health worker in Rasuwa. "The settlements next to the river have been completely swept away. Five of my own relatives are missing."

China has deployed at least 574 rescuers to the Gyirong land crossing, with a rescuer telling state broadcaster CCTV that 1.5-metre deep sediment is blocking pathways and could delay their arrival by four hours. President Xi Jinping has urged "all-out" search efforts and stronger monitoring to prevent secondary disasters.

Nepal's energy ministry said 430 MW of electricity supplies were affected, mostly from hydroelectric projects, representing more than 12% of the country's total hydropower capacity. Prime Minister Balendra Shah has ordered evacuations from lower areas, with police and military joining rescue efforts.

Indian Prime Minister Narendra Modi said New Delhi is ready to provide all possible humanitarian assistance, with teams from both countries coordinating closely. Flood alerts have been issued in the northern Indian states of Uttar Pradesh and Bihar, as the Bhote Koshi river flows into Nepal's Trishuli river and eventually into India as the Gandak river.

Last year's Bhote Koshi flood killed nine people and left 24 missing, washing away a "Friendship Bridge" linking Nepal and China and disrupting trade for months.