Deaths surge, 65 Americans among hundreds missing after Nepal floods

Rescue teams were searching for hundreds of missing people along the Nepal-China border Thursday after a catastrophic and deadly torrent of floods and mud swept through several communities a day earlier following a glacial collapse. The head of Nepal's tourism board told CBS News on Thursday that 65 U.S. nationals were among those missing in the wake of the disaster.

The National Disaster Risk Reduction and Management Authority in Nepal said 826 people were missing and the death toll from the country's flash floods rose to 165 on Thursday. Nepalese authorities ramped up operations in the worst-affected districts of Nuwakot and Rasuwa.

Chinese state broadcaster CCTV separately reported that 558 people were missing in Tibet — 260 of them foreigners — and two villagers were rescued. At least three people were reported killed as of Thursday morning, it said.

Hikmat Singh Ayer, CEO and senior director of Nepal's Tourism Board, told CBS News' Arshad R. Zargar on Thursday that at least 65 Americans were among the missing foreign nationals in the small Himalayan nation, almost doubling the number he reported missing the previous day.

Secretary of State Marco Rubio expressed U.S. solidarity on Wednesday with the Nepali people, saying in a social media post that the department "stands ready to support the government of Nepal with needed humanitarian assistance."

In a series of social media posts , the U.S. Embassy in Nepal expressed "heartfelt condolences to the families and loved ones of those who lost their lives in the devastating floods" and said it was "working to account for U.S. citizens who may have been affected."

The embassy urged U.S. nationals in the region who were able to contact their family, hotel, guide, trekking or tour company as soon as possible using any means, but noting that communications were still severely disrupted.

The U.S. State Department said it was is closely monitoring the situation and sending an adviser to the region to help with response efforts, as well as a $500,000 grant to Catholic Relief Services.

Flash floods decimated villages, slamming into houses, roads, bridges and power plants. Videos broadcast by regional news outlets and posted on social media show violent torrents of water surging through valleys and mountain passes, tearing down bridges and dams and sweeping away buildings.

Drone footage in Nepal on Wednesday showed roads destroyed and buildings buried by thundering water the color of wet cement.

The region's steep valleys are economic lifelines and travel corridors but are precarious when disaster strikes. Images showed what appeared to be the second floors of buildings in Nepal's hard-hit Nuwakot district slathered in mud after the torrent rushed by. Debris hung from tree branches and wires, vehicles were buried and some stunned survivors were caked in mud. The floods halted travel in some areas.

"When I reached Dhunge bazaar, in half an hour, the flood came and damaged all the market. People were preparing to go to office then," resident Shoyam Rajbhandari said. "How many people are missing or dead, we don't know."

Since early morning, army and private helicopters have been deployed.