The wall of water also swept away one of the main bridges linking Nepal and China over the Bhotekoshi river.

Deadly floods and landslides are common across South Asia during the monsoon season from June to September but experts say climate change is making them worse.

In Nepal, eight bodies have been recovered and 20 others -- 14 Nepalis and six Chinese -- are listed as missing, according to police.

"Our focus is on search and rescue efforts. We have rescued 57 people so far," Nepal police spokesperson Binod Ghimire told AFP.

China's state television CCTV reported that a "mudslide disaster" hit the border area around dawn on Tuesday, with 11 people missing on the Chinese side.

It said those were in addition to six Chinese construction workers swept away on the Nepal side.

Increasingly intense floods and droughts are a "distress signal" of what is to come as climate change makes the planet's water cycle ever more unpredictable, the UN's World Meteorological Organization said last year.

And the Kathmandu-based International Centre for Integrated Mountain Development (ICIMOD) warned in June that communities face heightened disaster risks this monsoon season.

"Rising temperatures and more extreme rain raise the risk of water-induced disasters such as floods, landslides, and debris flows," ICIMOD said.