Four key questions on Gyirong mudslide in Xizang

A mudslide that began on the Nepalese side of the border on Wednesday morning hit the Gyirong Port area in Gyirong county, Shigatse, Xizang autonomous region, leaving three people dead and 558 others missing as of 8 am Thursday. Rescue work is continuing.

How have rescue operations progressed?

Gyirong township lies on the southern slope of the Himalayas, bordering Nepal. Its steep terrain and narrow valleys have made rescue operations extremely difficult.

Rescuers said mud in the core disaster area was more than 1.5 meters deep, while possible ground subsidence further slowed the movement of personnel and machinery. The mudslide also destroyed sections of the river valley. Local police warned that rising temperatures around noon could increase geological risks and urged people to leave dangerous areas quickly.

Multiple rescue forces have been sent to the front line. The Ministry of Emergency Management dispatched teams to Xizang, and as of around 8 am on Thursday, the first group of 141 rescuers had arrived at Gyirong Port. A plateau-type Mi-171 helicopter had also reached the disaster area.

Forces from the Xizang Military Command, armed police, fire and rescue teams, the China Search and Rescue Team and China Anneng Group - which specializes in the engineering element of rescue operations - have joined the operation. Shigatse has activated a Level I emergency response for natural disaster relief.

Norbu Tsering, commander-in-chief of the disaster frontline command, deputy secretary of the Communist Party of China Shigatse Municipal Committee and acting mayor of Shigatse, said two villagers from Resuo Village had been rescued as of 8 am on Thursday.

What caused the disaster?

Experts at the Ministry of Natural Resources said the disaster was triggered by the collapse of a high-altitude glacier in Nepal. The falling ice rushed downhill at high speed, sweeping up moraine deposits and turning into a debris flow. It then entered the Donglin Zangbo River, forming a mudslide that struck Gyirong Port and continued downstream through the canyon.

Guo Zhaocheng, director of the geological disaster investigation and monitoring center at the China Aero Geophysical Survey and Remote Sensing Center for Natural Resources, described it as a chain reaction from ice collapse to debris flow and then mudslide.

The debris flow moved at an estimated speed of about 50 meters per second and affected an area more than 20 kilometers away.

Yao Tandong of the Chinese Academy of Sciences said glacier-related disasters are becoming more frequent, wider in range and more destructive amid global warming. In this case, disaster energy moved down the valley and was amplified downstream, increasing both damage and secondary risks.

Rescuers said the terrain encountered by the mudslide as it rushed downstream did little to slow or absorb its force, making its impact especially destructive when it reached Gyirong Port. They said the disaster originated in a high-altitude, complex mountainous area of Nepal, where source-area inspections are difficult and early warning signs are hard to detect.

Gyirong Port is a major trade channel between China and Nepal, with concentrated personnel, buildings and business activities. Rescuers said casualty figures may be higher because the disaster occurred during daytime working hours.

What challenges do rescuers face?

Rescuers said the main challenges are unstable terrain, damaged roads, poor weather and disrupted communications.

Local authorities said a barrier lake had formed upstream after the ice collapse, posing a threat to downstream rescue work. Mudslides were still occurring near Langdang Snow Mountain, and drones were being used to monitor the lake because of fast-flowing river water and unsafe ground conditions.

Road damage has also slowed rescue access. A section about 3 kilometers from the main disaster site was damaged. On Wednesday, with roads blocked, an advance team of more than 10 police and fire rescuers used three large machines but managed to advance only about 600 meters. Rain, fading light and deep river water further complicated the operation.

By Thursday morning, several local officials and front-line rescuers said the roadbed had been severely damaged, and the river remained deep and fast-flowing, adding to the difficulty of rescue work.

Communications and power were cut off in the affected area. Five base stations along the route from Gyirong Township to the border port were destroyed by floodwater. At around 4 pm on Thursday, communication signals were restored in Resuo Village, about 3 kilometers from Gyirong Port.

Meteorological authorities have forecast frequent rain in Gyirong county until Sunday, with heavy rain possible in some low-altitude southern townships, along with high temperature variation between night and day. Mountain torrents, mudslides and Mudslides may occur in some areas.

How are affected people being aided?

After the disaster, national authorities activated a Level-II emergency response for disaster relief, the second-highest in China's four-level disaster relief emergency response system, and the Ministry of Finance and the Ministry of Emergency Management allocated 120 million yuan ($17.85 million) in central disaster relief funds.

Local governments have organized evacuations and temporary resettlement. Police involved in rescue work have moved more than 300 Gyirong residents to safety.

Shigatse has allocated more than 15,000 relief items, including tents, blankets, cold-weather clothing, folding beds and daily necessities. Sixty-two temporary tents have been set up to meet basic living needs.

At a temporary settlement about 20 kilometers from Gyirong Port, each tent is equipped with beds, quilts and pillows. Power support equipment, emergency lighting and charging facilities are also available.

The National Health Commission is coordinating medical treatment, transfer of the injured and psychological support. Xizang has opened a 24-hour psychological assistance hotline, while hospitals, blood supply units and national emergency medical rescue teams are on standby.

Meteorological departments at four levels are increasing coordination, using satellite remote sensing and weather monitoring data to identify secondary disaster risks around the mudslide-hit area. Forecasts are being updated on a rolling basis to support rescue operations.

Experts warned that people should avoid valleys, river channels, low-lying areas and cliffside slopes during rainfall and remain alert to Mudslides and mudslides for 72 hours after rain ends.