By Tuesday, the Fuyang city government had sent 11 medical workers to Wangjiaba, and more than 100 policemen were on duty to hand out relief materials and fight the flood.

Zhang Fanghua, chief forecaster of the National Meteorological Center, said that a cyclone over the Yellow and Huaihe rivers caused the rain.

"The cyclone, a low-pressure weather system, accumulated surrounding water vapor like a water pump, and the system is commonly seen as an indicator of rainstorms," she said.