It was confirmed that a train passed about one minute before the structure collapsed at the Seosomun overpass demolition site in Seodaemun District, Seoul.
According to The Chosun Ilbo on the 28th, at about 2:30 p.m. on the 26th, a seven-car Mugunghwa train passed under the Seosomun overpass demolition site. It was being repositioned and had no passengers on board, but the collapse occurred one minute after the train passed. About five minutes before the collapse, a KTX train carrying about 40 passengers passed.
The Seosomun level crossing where the collapse debris fell is a key section used by KTX, regular trains, and commuter trains to move to the depot for maintenance. On weekdays, 346 trains pass per day, and even on weekends, 319 trains pass.
At the time of the incident, three people, including the site manager who went out for a safety inspection, died and three were injured, prompting criticism that safety measures were inadequate. Prosecutors and police formed a dedicated investigation team and are looking into possible negligence.
Train service was suspended on sections including Seoul Station to Haengsin Station due to the accident. The nationwide train operation rate fell to the 80% range compared with normal.