College students trapped in quake-hit Ya'an City of southwest China's Sichuan Province return to Xianyang Railway Station in Xianyang City, northwest China's Shaanxi Province, April 22, 2013. The students of the Xianyang Normal University paid a visit to Ya'an City at the time when a 7.0-magnitude earthquake jolted Lushan County of Ya'an in the morning on April 20. (Xinhua/Liu Xiao)

College students trapped in quake-hit Ya'an City of southwest China's Sichuan Province return to Xianyang Railway Station in Xianyang City, northwest China's Shaanxi Province, April 22, 2013. The students of the Xianyang Normal University paid a visit to Ya'an City at the time when a 7.0-magnitude earthquake jolted Lushan County of Ya'an in the morning on April 20. (Xinhua/Liu Xiao)