Heavy rains started on Friday evening and the precipitation was up to 186 mm in some areas, the official of the Dandong headquarters of flood control said.
The 1,100 people were evacuated since the areas they live were prone to landslides and mud-rock flows. A national highway was closed for four hours Sunday by a landslide triggered by the rains, the official said.
Hundreds of government officials and police were patrolling in the landslide-prone areas and help evacuate local residents.
Mines in two counties under the jurisdiction of the Dandong city were ordered to suspend operation, the official added. All the reservoirs in Dandong have been emptied for floodwater.
It would continue to rain for the coming five days in Dandong, according to forecasts by local meteorological authorities.