WATCH: Devastation and horror as flash flood hits Nepal-Tibet border

TRISHULI, Nepal/BEIJING —A huge wall of mud and rock collapsed into a river on the Himalayan border of Nepal and China's Tibet on Wednesday, triggering catastrophic flooding on the Nepali side that killed scores of people and left hundreds of tourists missing.

In a still-unfolding disaster, verified videos showed dozens of people swept away at the border, with authorities on both sides fearing far higher casualties and massive destruction.

Houses, roads and power projects were washed away in Nepal, while officials in Tibet said they feared "major casualties" after a mudslide hit a border land crossing in the county of Gyirong. —Reuters