Floodwater breached a reservoir in southern China and threatened others on Monday, as heavy rain pounded the region, forcing hundreds of people to flee to higher ground.
Chinese authorities urged caution and ordered rescue and evacuation operations, with Typhoon Maysak expected to bring more bad weather.
Officials established rescue-and-evacuation teams and warned residents to stay away from the affected regions, rivers and low-lying areas.
At about 11am on Monday, two sections of the dam at Liulan Reservoir in Hengzhou gave way.
Typhoon Maysak brings heavy rain, strong winds to southern China
The collapse created a 50-metre (164-foot) gap in the structure, sending a massive torrent of water rushing downstream, the China Business Network reported.