The latest death toll from the devastating flash flood along the Nepal-Tibet border was reported on Saturday to be over 600, as frantic rescue operations to search for hundreds of missing people entered a fourth day.

Figures from both countries put the number of missing close to 3,000, with 682 bodies recovered and reports of corpses swept as far downstream as India.

According to Nepal's disaster agency, the death toll there now stands at 675, with 2,426 people — including foreigners — still missing.

Across the border in Tibet, China's state news agency, Xinhua, has confirmed seven deaths and reported 554 missing individuals.

A glacial collapse on Wednesday sent rock, ice, mud and debris surging through the Himalayan mountain river systems below.

The flood swept through areas near the Chinese border, ravaging entire towns and damaging hydropower plants.

What is the status of rescue efforts in Nepal?

Rainy weather conditions are hindering aerial rescue operations in Nepal.

Nepal army spokesperson Raja Ram Basnet told the media on Saturday that helicopter operations were on hold until the weather improved.

Rescuers are battling thick layers of mud in the affected areas, which is making it difficult for helicopters to land and take off.

Tunnels in the mountainous region are also a challenge, Basnet said.

The army has located people trapped in a tunnel of the Trishuli 3A hydropower project in Nepal's Rasuwa District. Over 100 people are believed to be inside the tunnel filled with mud.

Basnet said that rescuers were struggling to locate the entry points of the tunnel and had made use of  baskets and ropes to reach some people. There are also limited places for helicopters to land in the area.

On Friday, Nepal's Army shared visuals of some people being rescued from the tunnel. The survivors were seen stuck in the mud, while officials crawled through the sludge and held out their hands to them.

On Saturday, Foreign Minister Shishir Khanal said a specialized tunnel rescue team had arrived from neighboring India and was ready to start work.

Nepalese authorities said the bodies of many flood victims have also been found dozens of kilometers from the disaster zone in Chitwan District in southern Nepal, which borders India.

Meanwhile, Indian authorities said they recovered the bodies of seven people who were swept downstream from Nepal and believe them to be flood victims.

Nepal needs help in technical areas, says foreign minister

Late on Friday, Nepal's Foreign Minister Shisir Khanal told the Reuters news agency that his country needed equipment, along with technical knowledge in tunnel rescue operations.

Khanal also told Reuters that Nepal did not need help with search and rescue operations but needed assistance in opening transport and communication lines in places where bridges were destroyed, identification of dead bodies, DNA testing and storage of bodies for a longer timeframe.

"We have already made requests for such ⁠specialized ​services and technical assistance in areas where we don't have enough expertise and technical know-how,"  ​Reuters quoted Khanal as saying.

Nepal's Foreign Ministry had on Friday declined foreign involvement in search and rescue.

Nepal's post-flood rebuilding estimated at $4-$5 billion

In another Reuters interview, Nepal's Finance Minister Swarnim Wagle said that the Himalayan nation may need $4 billion (€3.5 billion) ⁠to $5 billion ⁠to rebuild after the flood.

The estimate is equivalent ​to nearly a tenth of Nepal's economy.

"The initial estimate is ​between $4-$5 billion. Just an estimate," Wagle told Reuters, adding that the bill would be much less than what was needed in reconstruction after the disastrous 2015 earthquake — Nepal's worst ‌ recorded disaster.

"Loss and damage is being assessed," he said.

What do we know about rescue operations in Tibet?

In Gyirong, one of the hardest-hit areas in Tibet along the China-Nepal border, Beijing had temporarily halted its rescue efforts due to the risk of renewed flooding before announcing that the threat had waned.

China's Xinhua agency reported on Saturday morning that two villagers had been rescued in the Gyirong area.

The glacial collapse on Wednesday led to the formation of a barrier lake upstream due to debris dams. Experts warned that the lake had started to overflow.

On Saturday, Chinese authorities announced that the lake had begun to shrink.

China's state broadcaster, CCTV, cited the Ministry of Water Resources as saying that satellite imagery of the surface area of the lake in the Tsangpo River basin on Saturday morning showed a reduction of around 21,000 square meters compared to images from Thursday.

Authorities have also identified a larger body of water at the bottom of the glacier collapse.

"We estimate its area to be over 120,000 ⁠square ​meters, but its depth is currently unknown," Reuters quoted Chen Hongqi, a senior engineer at ​the Ministry of Natural Resources' Geological Disaster Technical Guidance Center, as saying.

Reuters also reported an official of Nepal's Disaster ​Management Authority as saying that flood risks will remain until the two lakes have fully drained.

Edited by: Dmytro Hubenko and Wesley Dockery 

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