Rescuers work in a sustaining operation of searching for survivors among debris in quake-hit Yushu County, Qinghai Province, April 16, 2010. A dragnet search for survivors is implemented throughly at all rescuing sites as the "golden 72 hours", a key surviving chance for buried people comes on Friday. Yushu was jolted by a 7.1-magnitude earthquake Wednesday morning, which has left at least 1144 people dead. [Zhang Xiaoli/Xinhua]