Electricians work at night for daily normal operation of high-speed railways

Electricians check the overhead electric wires for bullet trains in the Dongtucun Tunnel of the Inner Mongolia section of the Zhangjiakou-Hohhot high-speed railway in north China's Inner Mongolia Autonomous Region, April 17, 2018. The 35-member group of electricians check and maintain the electric system within the section every night after the last bullet train passes the railway line. Their work at late night offers safety guarantee for the daily normal operation of high-speed railways. (Xinhua/Lian Zhen)