Alpine Eco Trek said it has not been able to establish contact with 12 Britons who were booked on a tour to Mount Kailash and were in the region when the flash floods struck.
The company’s travel logs which were shared with the Press Association, with a 13-year-old girl the youngest person missing.
Four of the firm’s Nepali tour guides are also missing.
Mount Kailash – a peak in the Himalayas near the border between Nepal and Tibet – is considered the spiritual home of the Hindu god Shiva.
The journey to the mountain is part of the Kailash Mansarovar Yatra, a sacred pilgrimage for Hindus.
The pilgrimage had only recently resumed after being disrupted first by the pandemic and then by tensions between India and China.
The Trekkers’ Society said nine UK nationals on a pilgrimage to Mount Kailash are missing after they crossed the Nepal-Tibet border. Four males aged between 14 and 50, and five females aged 40 to 53 remain missing.
Himalayan Glacier US had 47 guests on a pilgrimage to Mount Kailash, with two in the group being British citizens.
Kailash Journeys reported 27 guests and staff were missing, with two British men in the group.
Fishtail Tours said one British person on its tour was missing.
The flood hit early on Wednesday in Rasuwa, just north of Nepal’s capital Kathmandu.
Preliminary information suggested it was caused by an earthquake, but the US Geological Survey said additional analysis indicated “the seismic energy was instead generated by a landslide.”
It said a magnitude 5.2 seismic event caused by a “glacial collapse and debris flow” occurred near the border at 08:37 local time on Wednesday.
