The numbers alone reflect the scale of the destruction: Hundreds of people are reported dead so far, with more than 1,400 others missing, and entire towns have been wiped out after floods swept the Himalayan region on the border between Nepal and Tibet on Wednesday.But for the survivors, it is the force of the deluge that haunts them. One minute, their lives were routine. The next, the world turned upside down.Rajan Khatri (41), a police officer posted at Syabrubesi, one of the riverside villages worst affected by the floods, said he had received a call at 9.10am local time from a friend warning him that a massive flash flood was heading downstream.He and his colleagues had no time to react. As soon as he hung up, high waves swept through the police station.The water flung him out of the building, and he lost consciousness.“One of my senior officers and I were together when the wave struck. I was thrown out, but he was unlucky and was buried or swept away,” he said, from a hospital bed in Kathmandu.Rescuers on a bulldozer search for survivors following flash floods in Trishuli, Nepal. Photograph: Ezra Acayan/Getty Images Structures damaged by the giant torrent of water, mud and ice that swept through a remote river valley in the Rasuwa district near Nepal’s border with Tibet. Photograph: Atul Loke/The New York Times