A glacier collapse on Wednesday unleashed a huge torrent of rock, ice, mud and debris through Himalayan mountain river systems, killing at least 579 people in Nepal and seven in China's Tibet.
The number of missing in Nepal has nearly doubled to 1924, the country's disaster authority said on Friday. At least 558 were missing in Tibet's Gyirong County, Chinese state broadcaster CCTV said on Thursday.
Of those missing in the disaster, at least 540 are foreigners, including 41 Australians.
Only on Friday were rescuers able to reach Gyirong. State media reported the Chinese team of 21 rescuers and a search-and-rescue dog crossed mountains and valleys and used ropes to navigate forests and cliffs after roads to the complex, hemmed in by steep Himalayan slopes, were destroyed.
More than 90,000 people are estimated to have been affected by the disaster, the Red Cross said.
The flooding led to the formation of a lake, which on Friday began overflowing into the Lhende Khola and Trishuli rivers.
The overflow sparked panic and warnings from authorities in Nepal, leading to rescue operations being suspended for about three hours. The risk prompted all Chinese rescue personnel and vehicles to withdraw as well, CCTV said.
Both resumed rescue operations after the threat eased, with Nepali officials saying that they were still hopeful of finding survivors.
Nepal is continuing to monitor two barrier lakes upstream of the flood zone, with an official warning that flood risks will persist until both lakes fully drain.
Satellite imagery showed the second lake growing larger with no visible outlet, raising concerns that water pressure could still be building.
China's state-run Xinhua news agency said the first barrier lake was reducing in size, citing analysis by the water resources ministry.
A Chinese government geohazards expert warned, however, the lake may be unstable and that more than 100 glacial lakes scattered throughout the area could pose a threat.
Wednesday's flood ripped through villages and valleys, destroying power stations, roads and bridges along a route that links Kathmandu with Lhasa in Tibet and is popular with trekkers and pilgrims.
Ten bodies were found in three places in the northern Indian state of Uttar Pradesh in rivers that flow down from Nepal, police told Reuters on Friday.
Earlier, Nepalese rescue teams used helicopters to search for survivors and drop emergency supplies to thousands cut off in towns and valleys.
Dibga Tamang was among the last people rescued from Rasuwa on Thursday, airlifted along with three others to an army camp in Nuwakot.
"All of our people have gone. They are dead," Tamang said.
"I have no one left waiting for me. Everything and everyone is gone. The end."
A large number of people arrived at an army base in the area seeking information about missing and dead family members. Bodies were brought into the barracks and lists of rescued people were posted outside. Around the world, relatives of those missing were desperate for information.
The United Nations and its partners were scaling up relief supplies, with 20,000 households estimated to need food assistance and more than 50,000 people emergency water and support, UN spokesman Stephane Dujarric said.
While offers of search-and-rescue assistance are pouring in, Nepal said it does not need help from other nations.
A South Korean rapid response team in Kathmandu has not been deployed because Nepal does not have a plan to accept foreign rescue yet, the foreign ministry in Seoul said.
The Kathmandu Post reported that India, China, the United States, Britain, Japan, South Korea, Sri Lanka and Bangladesh had asked the government to allow their search-and-rescue teams to assist.
with DPA
