The flash flood caused widespread damage to bridges, houses and roads and swept away villages, in what is emerging as one of the major natural disasters to hit the Himalayan nation this year.

Of the 291 foreign nationals reported missing, 105 are Indians, while the others include nationals of Australia, the Netherlands, the United States, Malaysia, the United Kingdom and South Africa, Nepal News reported, citing data from the country's Tourism Board.

The nationalities of several missing foreign tourists have not yet been ascertained.

While Nepali media reported the death toll at seven, China's Xinhua news agency put the figure at eight.

Four bodies were recovered in Nuwakot district and another four in Dhading district, Nepal Police spokesperson Abi Narayan Kafle told Xinhua.

Nepalese authorities have launched a large-scale search, rescue and relief operation, with 12 people evacuated so far.

A large number of people are still feared missing following the devastating flood.

Four Nepal Army helicopters and eight private helicopters have been mobilised for search and rescue operations, The Himalayan Times reported.

Meanwhile, 14 employees of the Rasuwa Customs Office in Timure remain unaccounted for, including 11 permanent staff and three contract employees, the newspaper reported.

The exact cause of the flash flood remains unknown. Authorities are investigating the possibility of a glacial lake outburst flood (GLOF), according to reports.

Speaking about the disaster, Yee Liang, a Chinese businessman based in Kathmandu, told the BBC: "Our logistics company has seven container trucks there, all staffed by Nepalese employees. We have lost contact with all of them. There is no signal, so we cannot reach anyone."

The extent of the damage on the Tibetan side remains unclear.

Meanwhile, Nepal Prime Minister Balendra Shah held an emergency meeting to assess the situation and review ongoing rescue and relief efforts.

"Today's meeting held at the Prime Minister and Council of Ministers, Singhadurbar, discussed with MPs from Rasuwa, Nuwakot, Dhading, Gorkha and Chitwan on flood damage, condition of settlements in coastal areas, rescue and relief work," the Prime Minister's official Facebook account said.

"During a discussion with MPs from flood affected areas, the Honorable Prime Minister informed that the government has been fully committed to the safety and relief of the affected citizens, the lower coastal region has been given a clear direction to the bodies to take additional caution and transfer the displaced to safe places immediately," the post added.