What we know about deadly Nepal-Tibet floods

Massive landslides and flash floods on the Nepal-Tibet border have caused widespread damage and left hundreds dead or missing.

Search and rescue operations are under way. Chinese state media has said there are significant casualties, while Nepalese officials anticipate “huge scale loss”.

Here is what we know so far.

Nepal Army via EPA A team of military officers carry a stretcher containing a survivor of the flooding towards a military helicopter in a clearing in Newakot on Wednesday. — Military teams were brought in to help with rescue and evacuation following the flooding on Wednesday

What caused the deadly landslide?

Nepal’s foreign minister initially said an earthquake was reported on the Tibet-Nepal border shortly before the landslide, suggesting it may have triggered the disaster.

The United States Geological Survey (USGS) had first reported the event as a magnitude 4.4 earthquake on Wednesday, but later confirmed the incident “was instead a glacial collapse and debris flow” that “caused subsequent catastrophic impacts downstream”.

Map showing the path of floodwaters along the Trishuli River in northern Nepal after a glacier collapse near the Tibet border. The collapse sent ice and rock debris into the river, triggering flooding that destroyed a border checkpoint and continued downstream past Syrapu Besi. An inset map locates the affected area north of Kathmandu.

“Additional analysis of nearby seismic stations, long period seismic waves, and satellite imagery led to the determination that the seismic event was instead a glacial collapse and debris flow, and that no earthquake had occurred,” USGS said on Thursday.

Earlier Nepali authorities had also told the BBC that a massive chunk of ice may have collapsed from a mountain, pulling down rocks and other sediments with it.

Climate change is known to be driving faster glacier melt in the Hindu Kush Himalaya region and, as rescue efforts continue, scientists are trying to piece together the exact order of events.

Simon Cook, senior lecturer in energy environment and security at the University of Dundee who specialises in glaciology, said “climate change could have an impact”.

Cook said his team had detected that the lower part of a glacier in Nepal near the Langtang Lirung peak – which is approximately 15km (9 miles) west of the site of the floods – had collapsed.