Authorities in Nepal and Tibet have said they fear the death toll from catastrophic flooding could be much higher than 160 people already killed, as search and rescue efforts to locate the hundreds missing continue.

A huge wall of mud and rock collapsed into a river on the Himalayan border of Nepal and Tibet on Wednesday, triggering the flash flood that washed away houses, roads and border crossings.

Verified videos showed dozens of people swept away at the border, with authorities on both sides ⁠fearing far higher casualties and massive destruction.

Officials in Tibet said they feared “major casualties” after a mudslide hit a border land crossing in the county of Gyirong.

As darkness fell, authorities continued the grim task of recovering ‌and trying to identify bodies.

Nepal police said 157 bodies had been recovered ‌so far. Three people were reported killed on the Tibet side of the border.

Initial reports from Nepali officials suggested an earthquake in the area could have caused the lower part of a glacier to collapse and trigger the floods. The USGS later said the tremor recorded at the time was caused ​by the glacial rock and ice collapsing to the valley floor.

Here’s what else is happening:

• Rescue teams are rushing on Thursday to find hundreds of people missing after the flood and landslides killed at least 160 people. Many of the missing were foreign tourists, officials said.

• Nepali police said they had recovered 157 bodies after “devastating floods”, with officers working to move families in flood-risk areas to safety. Chinese state media reported “major casualties” from a mudslide at a Tibet border hub, reporting three dead and another 265 missing.

• Tibet government officials mobilised nearly 800 emergency workers and 150 vehicles as well as sniffer dogs and speed boats to help the rescue efforts, China’s official Xinhua news agency said.

• At least 403 tourists – 341 of them foreigners – were unaccounted for several hours after the disaster struck on Wednesday morning, according to Nepal’s tourism ministry. The missing foreigners included 142 Indians, 33 from the UK, 47 from the US, 34 from Australia and 24 from Canada as well as others from South Korea, the Netherlands, Malaysia, Portugal and South Africa, the tourism board said. Nine ⁠South Koreans ⁠were missing, Seoul’s foreign ministry said.

• At least 28 Nepal police officials were missing, a police spokesperson said.

• Entire villages and markets were “wiped out”, the International Federation of Red Cross and Red Crescent Societies said. It was dispatching emergency supplies including blankets, first aid kits, stretchers and body bags.

• United Nations chief António Guterres said UN ⁠teams ​and ‌partners ‌were ‌mobilising supplies and personnel in Nepal ‌to support affected communities.

• Surveillance video from the Chinese side of the border showed a raging wall of mud and debris crashing over a building several storeys high, engulfing it as dozens of people flee for their lives below. The surge swept away buses and cars.

• Experts warned that a lingering blockage upstream on the Nepal-China border river could produce a second flood.

• The cause of the flooding was not immediately clear. Nepalese foreign minister Shishir Khanal said an earthquake likely triggered a landslide, which in turn blocked a river, sending water gushing downstream. Nepal’s disaster authority said satellite data indicated a “snow-rock landslide” on the Nepal-China border may have caused the flood. Scientists say climate change is increasing the frequency and intensity of extreme weather events in the region.

• Chinese leader Xi Jinping said “the most urgent task is doing everything possible to search for and rescue the missing people”, according to Chinese state broadcaster CCTV.

• The US Geological Survey first reported a magnitude-4.4 earthquake early on Wednesday, about 66km (41 miles) north of Kathmandu, near the border. It later updated to call the shaking a 5.2-magnitude landslide.