Summary
The death toll in Nepal has risen to 547, officials say, after Wednesday’s flash flooding devastated the Himalayan border region
Chinese officials say that search and rescue operations have reached a “critical stage”, as a lake formed by a landslide is at risk of overflowing
Nepalese officials say more than 100 foreign nationals have been rescued. Earlier, they said more than 500 were missing
In Tibet, five people have died and more than 558 are missing, Chinese state media say. It is not clear if the latest figures overlap
“Please help us find her” – the brother of one of the missing Britons appeals to local officials to help locate his sister
A collapsed glacier caused the huge flood wave, local officials tell the BBC. The surge tore through houses and roads, and destroyed a key Nepal-Tibet border crossing
Drone video captures moment of glacier collapse
By Charlotte Green and Benedict Garman
BBC Verify has authenticated two videos which show the moment of a glacier collapse in the Himalayas which triggered the deadly Nepal-Tibet floods.
The videos, filmed by a drone and posted to the Chinese social media platform Xiaohongshu, capture the landslide near the Langtang Lirung peak, more than 7,200m (23,600ft) above sea level.
Plumes of dust can be seen rising into the air near the snow-covered mountains.
The location of the clips match the direction of the floodwater which surged down the Trishuli river, devastating villages and communities along its way.
‘Dams of this kind often fail’: A closer look at what could happen to the barrier lake
Mark Poynting
Climate and science reporter
As we’ve been reporting, a barrier lake has formed in the region, where water has been collecting behind a natural dam of loose rock and mud.
One possibility is the water could slowly spill over the crest of the dam or seep through the rocks, which would allow the lake to gradually drain away.
But the fear is that could also destabilise the dam, potentially causing it to suddenly break apart.
This could allow much of the lake water to be released at once.
Unlike an engineered dam, this barrier has no spillway and no solid core,” says Dr Fatima Pillosu of the University of Reading.
“So, dams of this kind often fail, many within days or weeks of forming,” she adds.
Scientists will be closely monitoring the lake’s water levels and any changes to the structure of the dam.
But they say it’s not possible to predict exactly when – or even whether – a sudden collapse will happen.
We’ve got more detail on the barrier lake in a separate story here.
The lake of flood water and debris prompting fears of a second flood in Nepal
China has warned there is a “high risk” that a lake which formed after the landslide could breach its banks.
A type of barrier lake, a body of water formed when debris dams a river, concerns over its levels saw rescue efforts temporarily suspended today, but they have since resumed.
In the video below, our China correspondent Laura Bicker talks you through why officials are so concerned about it.
