Four people died and more than 127,000 were evacuated after torrential rains lashed China's north-east Liaoning Province on Sunday, causing flooding along the border with North Korea, dpa reported.
The Yalu River, which marks the border, breached a dike, washing into buildings in Dandong City, the state-run Xinhua news agency reported.
The floodwaters destroyed an estimated 3,000 houses and damaged 5,000, as economic losses reached 112 million dollars, the Ministry of Civil affairs said.
Since flooding began on August 19, 457,000 people had been affected, the Ministry said.
Around 5,000 North Koreans were evacuated from the border area, according to the state-run Korean Central News Agency.
Relief efforts on the Chinese side were hampered by ongoing rain, and workers were rushing to build sand-bag flood barriers, Xinhua said.
The central Dandong district had not been affected yet, as it was protected by a secondary dike.
Rain was expected to continue until Monday, according to the provincial flood relief headquarters.
China is facing its worst floods in at least a decade, Xinhua reported, with relief operations under way in a number of regions hit by rain-induced floods and landslides in recent weeks.