A rapid hazard assessment by international scientists found that there were early warning signs of the Nepal-Tibet disaster, including changes in the surface of the collapsed glacier. However, no early warning system for glacier-related hazards had been set up in the affected area. Hundreds of construction workers were trapped at several hydropower projects after the deadly floods, and early warning systems for construction workers were described as 'very weak'. China and Nepal have launched a number of high-altitude infrastructure projects in the past decade, including hydropower plants along the border, several of which were damaged by the flash flood. The number of people missing has risen to over 3,900 with at least 1,000 people known to have died. Experts say there needs to be better early warning systems in disaster-prone areas, including risk assessment beyond the infrastructure project borders.