We have been reporting that risks of new flooding persist on the Nepal-Tibet border, further complicating rescue efforts.

Now, Chinese state news agency Xinhua has said that a lake formed after the flash floods is at "high risk of breaching and sending floodwaters downstream', according to the AFP news agency.

Forecasts suggest "inflows into the lake could reach about 3 million cubic meters (3bn litres) over the next three days amid continued rainfall" - the equivalent of 1,200 Olympic-sized swimming pools.

This could "potentially cause further damage in areas including Gyirong Port and elsewhere downstream", the state news agency added.

On Wednesday morning, a huge surge of mud and water swept down from the Nepal-Tibet border, leaving destruction in its path. Since then, the number of dead and missing has climbed, with rescue efforts made more challenging by fears of a second flood.

This is how the last nearly 48 hours have developed:

Wednesday

08:37 local time in Nepal (02:52 GMT): A magnitude 5.2 seismic event occurs near the Nepal-Tibet border. This was initially thought to be an earthquake, but the US Geological Survey (USGS) has since said it was a glacial collapse.

The USGS says the flow of debris from the collapse led to "subsequent catastrophic impacts downstream".

Moments later: A wall of water and other material crashes downstream, taking buildings, roads and vehicles in its wake.

14:45: Authorities say 384 tourists are missing, including 291 foreign nationals. Nepalese authorities later confirm that 33 Britons are among those missing.

By 17:00: Nepalese police tells the BBC that at least 17 people have been killed.

22:45: The Nepalese prime minister's office says search and rescue operations will continue throughout the night, with civilian and military personnel mobilised.

Thursday

By 08:00 local time (00:00 GMT) in Tibet: China says three people were killed on the Tibetan side, while 558 others are missing.

Shortly after 07:15 (01:30 GMT) in Nepal: Nepalese police say they have recovered 162 bodies so far. This figure has continued to rise throughout the day - and currently stands at 389.

Mid-morning: The Dalai Lama, the spiritual leader who lives in exile from Tibet, says he is praying "for all those who have lost their lives".

14:00 in Nepal: An update from authorities puts the number of missing people at more than 900, including more than 500 foreign nationals.

Around 18:30 in Nepal, the Chinese Ministry of Water Resources says it is preparing for the possibility that a lake of rising water that has formed along the China-Nepal border to burst its banks.

After midnight, Nepal's officials tell the BBC the glacial collapse that caused the flood took place on the Nepali side of the Himalayan mountains, not in Tibet on the Chinese side.

Friday

Around 01:00, Nepal's prime minister's office says 350 people have been rescued from a tunnel near the Trishuli river, as the army works to rescue 100 others inside.

It has just turned 06:45 in Nepal where rescue efforts continue for the hundreds still missing.

The deadly path of the Nepal-Tibet flash floodpublished at 01:44 BST

01:44 BST

By Merlyn Thomas

Using verified videos and satellite imagery, we trace the path of the deadly flash floods that have devastated the Nepal-Tibet border region.

Soutik Biswas
India Correspondent

The devastation in Nepal also serves as a warning for India.

Nepal’s Himalayan rivers feed several major Indian river systems, including the Gandaki and Kosi, as well as the Bagmati, Kamla-Balan and others, before flowing into the densely populated plains of Bihar and eastern Uttar Pradesh.

Bihar, India's most flood-prone state, is unusually exposed. Only about 35% of the land that supplies water - through rainfall, streams and smaller rivers - to major north Bihar rivers lies within the state and a lot of the rest is across the border in Nepal and Tibet, according to the government.

Wednesday's catastrophe - which is said to be caused by a glacial collapse that sent a huge debris-filled surge downstream - shows the risk.

Floods don't simply carry water: they carry enormous amounts of sediment, raising river beds and threatening embankments. So what begins as a Himalayan disaster could become an Indian flood emergency.

A woman from Berkshire has been named as one of the 33 British nationals missing after devastating flash floods in Nepal.

Fishtail Tours and Travels confirmed Leena Bector, from Slough, was among 27 travellers linked to the tour company who remain unaccounted for.

Her husband, Bhupesh Bector, told The Times: "I know that she's in Nepal for sure, so even if they find her today or tomorrow, I need to be there."

In an update on Thursday evening, Nepal Police said 389 bodies had been recovered, while the number of people injured and rescued had risen to 466.

You can read more in our story here.

Gabriela Pomeroy
Live reporter

Image source, Bhavesh Ramjee

South African businesswoman Bavika Ramjee was “really excited and thrilled” to go on her first Hindu pilgrimage with the tour group Kailash Journeys.

“It was life-long ambition,” her brother Bhavesh tells me from his home in East London, "as she is very spiritual and religious."

But since the tour group reached the border between Nepal and Tibet on the same day the floods hit, they’ve been completely out of contact.

Bhavesh says in a shaking voice: “We've been contacting the embassy, looking through lists of missing people, trying all avenues to get any information."

"It's been awful," he says.

Simon Atkinson
Australia reporter

We've had an update from Australia's Foreign Minister Penny Wong that at least 39 Australians are among those reported missing - up from the 35 we were told yesterday.

The additional four people were travelling separately to the organised tours we knew about earlier and Senator Wong says there is an "unfortunate possibility" that the number will rise.

"I know this is an extremely distressing time for those who have loved ones unaccounted for and we are thinking of them," she tells the ABC.

Australia will send three humanitarian response specialists "within the next 48 hours" to assist Australian staff already there, Wong added in a separate statement. The country has also pledged a A$5m (£2.65m) assistance package for affected communities.

We know that among the missing Australians are two boys aged 11 and 14 who were travelling with their parents - among 15 Australians on a tour organised by Himalayan Glaciers US. That entire group of 47 is still to be accounted for.

David Fisher, head of delegation for the Red Cross in Nepal, tells BBC News that secondary flood warnings have put people "very much on edge".

"People of course remain in shock from this terrible, terrible disaster," he says.

Asked how it is impacting relief planning, he says Red Cross teams are going "truck by truck" and haven't brought in the vast bulk of goods from their Kathmandu warehouse yet.

"What we’re most worried about is the danger to the lives of people who are still in the path of this potential future flood," he adds.

Fears new lake of rising water in China could burst its bankspublished at 23:00 BST 27 August

23:00 BST 27 August

Laura Bicker
China correspondent

A lake of rising water has formed at a site along the China-Nepal border prompting fears that it could burst its banks - just as rescuers try to find survivors after yesterday’s landslide.

Chinese search teams in Tibet have spent the day assessing the risk of flooding near Gyirong port after a lake formed near the confluence of Nepal’s Chochen river and the Puruchangpo Zangbo river.

They told state media that stabilising this body of water was a priority to keep rescue personnel on the ground safe.

China’s Ministry of Water Resources has used modelling techniques to estimate how much water is in the lake and now say that with continued rainfall, there is a high risk it could burst within the next three days.

The ministry said it will prepare for a potential breach and provide support for emergency rescue efforts.

Image source, Getty Images

Since the floods first struck the region on Wednesday, the numbers of people killed and missing has continued to climb.

Authorities in Nepal and state media in China - which governs Tibet - have been giving updates, although it's not clear if the figures overlap.

Here's what we know, according to the most recent updates:

In Nepal

• The number of people killed in Nepal has risen to 389, Nepal police say
• Meanwhile, 910 people are missing, according to Nepal's National Disaster Risk Reduction and Management Authority
• Among the missing are 517 foreign citizens, 44 members of the Nepal Army and 28 Nepal police officers

In Tibet

• Three people are confirmed to have died, according to China's state broadcaster CCTV
• And 558 people are missing, with 260 foreign nationals among them, CCTV says

Image source, AP

Rescue efforts are continuing for a second night in Nepal and Tibet, almost 48 hours after a catastrophic flash flood tore through the Himalayan border area.

The number of people dead and missing has continued to climb since the flood first struck on Wednesday.

More than 900 people are missing and at least 389 have died in Nepal, while three people are confirmed to have been killed in Tibet and more than 550 are unaccounted for. However, it's not clear if these figures overlap.

Meanwhile, analysts and monitoring bodies are warning of the potential for further flooding in the area, where the significant damage to infrastructure is already hampering rescue and recovery operations.