A huge piece of ice that fell thousands of metres from a glacier into a river below may have unleashed the disaster in Nepal and Tibet that killed at least 270 people. Read moreNepal-Tibet floods live: Nearly 1,500 people missing in devastating landslides Here is what experts believe happened so far: Glacier collapse A glacier collapse in Nepal's mountains near Tibet appears to have triggered the disaster. "A large chunk of glacier fell from about 5,200 metres (about 17,600 feet) ... into a valley," said Simon Cox, principal scientist at New Zealand's GNS Science. It "transformed into this raging mass of debris ... where it picks up rocks and sediment and trees and anything in the way and fires it on down through the canyon," he told AFP. The wall of water first impacted a border post, as documented in terrifying CCTV footage showing mud and debris engulfing the area as people fled before it. It then travelled downstream into Nepal, flooding villages and bringing down bridges and buildings. Seismic activity
(COMBO) This combination of satellite images by Planet Labs created on August 26, 2026 shows an aerial view of the Shyaphrubesi village and Trishuli River in Rasuwa district of Nepal before the flood on August 23, 2026 (top) and after the flood on August 26, 2026 (bottom) © - / 2026 Planet Labs PBC/AFP
