Trainer Zhang Chenyuan takes a police dog to search for explosive at Yinchuan Railway Station in Yinchuan, capital of northwest China's Ningxia Hui Autonomous Region, Jan. 10, 2017. Police dogs are allocated to travelling stations during the annual Spring Festival travel rush, when most of the Chinese people return to their hometown for family reunion. The Spring Festival, or Chinese Lunar New Year, falls on Jan. 28 this year.(Xinhua/Peng Zhaozhi)