China's Ministry of Water Resources has warned that another 3 million cubic metres of water could flow into the already lake over the next three daysA lake formed by a landslide on the Nepal-China border began overflowing on Friday, triggering a fresh flood alert and forcing Nepal to temporarily suspend rescue operations in areas devastated by a flash flood two days ago.Nepal and China have both warned of fresh flooding after Wednesday's catastrophic flash flood killed at least 469 people in Nepal and left nearly 1,000 missing. The disaster was triggered after a glacier collapse in the Himalayas sent huge amounts of ice, rock and water downstream, devastating settlements, bridges and hydropower projects.Chinese authorities said on Friday that the newly formed lake had grown to more than 2.5 million cubic metres of water, up from an estimated 1.5-2 million cubic metres recorded a day earlier. The rising water has already forced Chinese rescue personnel and vehicles to withdraw to a safer area amid fears of a breach and further landslides and avalanches.Why is a second flood feared?Experts are particularly concerned because debris from Wednesday's disaster may have created another temporary blockage in Nepal's Trishuli river. The International Centre for Integrated Mountain Development (ICIMOD) is assessing whether the debris has formed a landslide dam, which could trap large amounts of water upstream before suddenly releasing it.“With a blockage still lodged upstream on the Nepal-China border, authorities warn a second flood is imminent,” Qianggong Zhang, head of climate and environmental risks at ICIMOD, told The Independent, which reported that evacuation orders had been issued for Jilong Port because of the risk of another wave of flooding.The danger is not limited to the lake itself. A sudden breach could send a powerful surge downstream through an already devastated landscape, while the unstable terrain could trigger further landslides, mountain collapses and avalanches.China's Ministry of Water Resources has warned that another 3 million cubic metres of water could flow into the already dammed lake over the next three days — roughly equivalent to 1,200 Olympic-sized swimming pools. Chinese state media said peak flow was expected around September 1, while rainfall forecast over the coming week could further increase the threat.“The volume of water is continuing to increase, and so is the risk,” Zhu Jinfeng, a researcher with the ministry's hydrology department, told CCTV.Chinese authorities have deployed an eight-member engineering team to conduct aerial surveys and 3D modelling of the lake. Engineer Chen Hanxiao said access to the site was difficult because the glacier collapse had left isolated and steep cliffs around the shoreline.Nepal races to rescue survivors as threat growsThe warnings come as Nepal's rescue operation enters its third day. Nepal Police said 469 people had died across eight districts, while 977 people, including security personnel and foreign tourists, remained missing. A further 1,545 people have been rescued.More than 7,400 security personnel have been deployed, with helicopters being used to evacuate people from isolated areas and ground teams searching riverbanks and downstream settlements. The Nepal Army has also sent a team to inspect the Bhotekoshi River amid concerns about further flooding.The disaster has already left entire communities buried under mud and debris. At the Upper Trishuli-1 Hydropower Project, rescuers were searching for people believed to be trapped inside a tunnel, although mud had covered its entry and exit points.