Flash floods that struck Nepal and Tibet have killed ‌at least 162 people but authorities on both sides fear the final number of casualties will be ‌far higher amid massive destruction.

Here is a look at what caused the calamity, and where ‌things stand.

WHAT HAPPENED?

On Wednesday, the lower part of a glacier in the Himalayas collapsed and crashed onto the valley floor, possibly triggered by an earthquake

An avalanche of ice and rock swept down the Lhende Khola river, which runs along the mountainous Nepal/Tibet border

The mudslide slammed ‌into Gyirong port ‌in Tibet ⁠and into Nepal, creating high-speed flash floods that washed away entire roads ​and power projects and inundated villages

HOW MANY ARE DEAD AND MISSING?

Authorities have recovered 162 bodies so far, but the death toll is expected to rise sharply

It is unclear how many overall are missing. The missing reportedly include over 400 foreign visitors, including 133 Indians on a pilgrimage, ⁠47 Americans, 34 Australians, 33 British, five Japanese and 24 ‌Canadians

​Nine South Koreans working on a hydropower plant are unaccounted for, and citizens of Malaysia and ​South Africa were ‌also reported missing

About 5000 people were evacuated in the Indian state of Bihar after ​flood alerts were issued

WHAT IS THE SITUATION NOW?

Police and military personnel are conducting rescue efforts, although officials have said rescue helicopters will not be able to land ​in ​some of the affected areas until ​the waters recede

People living in low-lying regions have been moved to safer places, and those along the river have been advised to remain alert

The United Nations has said it is mobilising supplies and personnel to support affected communities. India said ​it was coordinating closely with Kathmandu on rescue and relief efforts, and South Korea is sending ​a rapid-response team