Rescue workers search for victims after a mud slide swept into the town of Zhouqu in Gannan prefecture of northwestern China's Gansu province, Wednesday, Aug. 11, 2010. The disaster in China's Gansu province was caused when a debris-blocked swollen river burst, swamping entire mountain villages. (AP Photo/Ng Han Guan)

Photo by: Ng Han Guan

Rescue workers search for victims after a mud slide swept into the town of Zhouqu in Gannan prefecture of northwestern China's Gansu province, Wednesday, Aug. 11, 2010. The disaster in China's Gansu province was caused when a debris-blocked swollen river burst, swamping entire mountain villages. (AP Photo/Ng Han Guan)