A team investigating a derailed bullet train in Gangwon Province has tentatively concluded that an error in the railroad switch system that controls the tracks likely caused the derailment.

Land, Infrastructure and Transport Minister Kim Hyun-mee on Sunday received the report from Korea Railroad Corporation CEO Oh Young-sik during her visit to the site of the derailed KTX train.

A Seoul-bound KTX with 198 passengers aboard went off the tracks minutes after departing from Gangneung early Saturday. A total of 15 passengers suffered minor injuries.

Transport ministry officials reportedly said on Saturday that an error in the signaling control system, which controls the railroad switch system, probably caused the accident.

The railroad switch system and the signaling control system for the Gangneung-Seoul section were reportedly installed in June last year.

KTX operations on the Jinbu-Gangneung section remain suspended, while other trains are running as scheduled from Seoul to Jinbu. Currently, authorities are operating 46 buses to transport passengers between Jinbu and Gangneung.

Meanwhile, work is continuing on Sunday to restore the damaged tracks, with the derailed locomotive and one of the ten cars removed from the rails, and the remaining cars placed back on the train tracks.