A KTX high-speed train derailed on Friday afternoon near Gwangmyeong Station, southwest of Seoul because workers improperly repaired a point along the tracks. The Ministry of Land, Transport and Maritime Affairs is investigating those involved.
Between 1:30 a.m. and 4:30 a.m., mechanics with a repair contractor replaced a cable in the switch box and failed to properly tighten a nut measuring 7 mm in width, causing warning signs to appear at the control center in Guro, Seoul, a ministry official said. At around 7:30 a.m., KORAIL staff inspected the site but failed to discover the loose nut and set the track straight.
But the KORAIL workers failed to report this to the control center, which signaled a KTX-Sancheon train headed for Gwangmyeong to shift tracks, leading to the derailment, according to the ministry.
The accident could have been avoided if the train, like most trains, had gone straight and then turned around and returned to the station to drop off the passengers. But the train from Busan to Gwangmyeong was three minutes late, so the control center signaled the train to shift tracks right to Gwangmyeong Station to save time.
"It was an accident caused by a communication mistake," the official said. "There were no problems with the train according to our investigation."