Dozens of people were confirmed dead and hundreds more are missing after a flash flood swept through remote valleys in Nepal and Tibet on Wednesday.

Police spokesman Abi Narayan Kafle told French news agency AFP that at least 95 people had been killed, and that 28 police personnel were missing.

The floodwaters washed away villages, damaged bridges and destroyed electrical infrastructure on both sides of the Nepal-China border.

"There is devastation everywhere we look," ‌Tula ​Bahadur BK, a health worker in Rasuwa district, told Reuters.

"The settlements next to the river have been completely swept away. Five of my own relatives are missing."

At the same time, Chinese authorities also reported that a mudslide caused "major casualties" on the other side of the border in Tibet.

Hundreds of people missing

Nepal's Tourism Board said 384 travelers were reported missing. 

Among those missing travelers were including 291 foreign nationals, inculding 105 Indians.

A Nepali police spokesperson told Germany's DPA news agency that dozens of personnel were also missing.

"So far, we only have confirmation of 26 police personnel who remain missing in the flood," they said.

"We also have missing information of government revenue officials, hydropower workers among others. But we are still collecting the data."

What caused the flash floods?

Nepal's Foreign Minister Shisir Khanal said an earthquake triggered an avalanche in the Himalayas that then triggered flash floods in the valleys below.

Chinese state news agency Xinhua said a mudslide on the Nepali side of the mountains spread to Gyirong County in Tibet.

Major rescue operations underway

Nepal dispatched more than a dozen rescue helicopters to the mountainous Rasuwa region, but floodwaters were too high for the helicopters to land.

Nepali Prime Minister Balendra Shah said the military and police were assisting with rescues.

"Instructions have been given ... to move ​the people living in the lower areas ⁠to safer places," he said. "People along the river are advised to exercise extra caution and remain alert."

Chinese President Xi Jinping also ordered an "all out" rescue effort.

He said "the most urgent task is doing everything possible to search for and rescue the missing people... quickly treat injured people and minimize casualties to the greatest extent possible," according to Chinese state media.

A second flood may be imminent, according to Qianggong Zhang, head of climate and environmental risks at the International Centre for Integrated Mountain Development.

"With a blockage still lodged upstream on the Nepal-China border river, authorities warn a second flood may occur," he told the AFP news agency.

Edited by: Wesley Dockery 

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