Thousands driven from their homes as monsoon rains cause devastation across China. A state of emergency has been declared in the provinces of Hubei, Hunan, Jiangsu and Anhui. The government has already moved tens of thousands of people from low-lying areas along the Yellow River. Chinese authorities have warned that much wider damage could be caused if the Yellow River floods, since it runs high above the surrounding countryside due to heavy silting. Each summer floods triggered by seasonal rains devastate wide areas of China. Millions of people remain vulnerable to waterborne diseases.