China has warned of a high risk that a lake formed by a landslide near the China-Nepal border could overflow and send floodwaters downstream. State media, citing water resources authorities, said the lake was created after a large flow of mud and debris struck the Gyirong area bordering Tibet on Wednesday. Reports said hundreds of people remain missing after the incident.

CCTV said water levels could rise over the next three days and may reach their highest level around September 1. Xinhua, citing water authorities on Thursday night, reported that continued rainfall could bring about 3 million cubic metres of water into the lake during that period.

Authorities said the increased inflow would raise the danger of the lake’s barrier breaking, potentially causing further damage in downstream areas, including Gyirong port. Rain is forecast in the area for the next three days. By Friday morning, 499 local residents and 555 tourists had been moved to safer locations, CCTV reported. The nationalities of the tourists were not disclosed.