Twenty-two persons have been confirmed dead and dozens remain missing after a flash flood in Bhotekoshi river swept through settlements across Rasuwa and neighbouring districts on Wednesday.

As many as 384 people, including 291 foreign nationals and 32 security personnel, have been out of contact, according to Nepal Tourism Board.

Riverside settlements in Rasuwa and Nuwakot districts are hit the hardest. “Entire settlements have been decimated, while banks, bridges, and markets have incurred major damages,” said Krishna Prasad Humagain, Nuwakot’s assistant chief district officer. Dozens of concrete bridges have been swept away. “There has never been this much damage in history.”

Search and rescue teams have been deployed across the affected areas. Inclement weather and disruptions in communications have made search-and-rescue operations difficult, local authorities say.

The flood has left 60 people associated with the 20-megawatt Langtang Khola Hydropower Project out of contact, according to project promoter Bijay Mohan Bhattarai.

Twenty-five engineers, drivers and kitchen staff and 35 workers who were inside a tunnel have been out of contact since Wednesday morning, Bhattarai said.

“We have not been able to contact them so far,” Bhattarai said on Wednesday afternoon.

The hydropower project had been completed and was scheduled to undergo testing in two days, Bhattarai said.

Meanwhile, 15 employees of the Rasuwa Customs Office in Timure are also missing, according to Rajendra Dhungana, chief of the customs office.

The Nepali Army has rescued 88 people caught in the flood, army spokesperson Rajaram Basnet said. Thirteen of those rescued have been admitted to Tribhuvan University Teaching Hospital in Kathmandu for treatment, while the others have been moved to safety. Some injured people are receiving treatment at Trishuli Camp, he said.

Twelve helicopters, including four operated by the Nepali Army and others by private companies, had been deployed for the rescue operation.

Rescue flights have been repeatedly disrupted by poor weather. As many as 29 private and six military helicopter flights have so far been made from Tribhuvan International Airport in Kathmandu to the flood-hit areas of Rasuwa, according to the airport’s rescue coordination centre. Of those, 23 private and two military helicopters returned to Kathmandu carrying injured people.

Three helicopters carrying rescue and relief supplies to Rasuwa were also forced to turn back because of bad weather. The airport said adverse weather was also making it difficult to send additional helicopters into the affected areas.

Home Minister Sudan Gurung and Minister for Culture, Tourism and Civil Aviation Khadak Raj Paudel have been coordinating rescue and relief flights from the Kathmandu airport.