The sudden surge caused catastrophic downstream impacts in Nepal and Tibet, with many people, including foreign tourists, still reported missing.Nepal’s Foreign Minister Shishir Khanal had initially suggested that an earthquake may have triggered a landslide that blocked a river before unleashing a destructive wall of water.Other possible explanations included a glacial lake outburst flood or an ice avalanche, as rescue teams continued searching for survivors and missing people.About 403 people, including 341 foreign nationals, are reported missing as the scale of the crisis continues to grow following a catastrophic flash flood that devastated the Nepal-China border region, sweeping away homes, roads, bridges and vital infrastructure in one of the Himalayas’ deadliest disasters in years. Video: AFP