On Arbor Day, April 5, a passenger who missed his stop on Seoul Subway Line 1 opened a train door and climbed down onto the tracks, causing a brief disruption to service. In Busan, ground subsidence on several roads led to severe traffic congestion.
According to Seoul Metro, a man in his 50s identified only as "A" used an emergency release lever to open the door of a train stopped at Cheongnyangni Station at around 5:20 p.m. and trespassed onto the tracks. He climbed back up to the platform through a gap near the locomotive cabin. Investigators determined that he took the action after failing to exit the train at Cheongnyangni Station, which was the train's terminal stop. Station staff confirmed the incident at around 5:30 p.m. and took action. During that time, the northbound line toward Gwangundae Station was delayed by approximately 13 minutes and the southbound line by approximately five minutes, Seoul Metro said. Trains are currently operating normally in both directions.
Meanwhile, the Busan city government sent multiple disaster safety text alerts during the afternoon, notifying residents that some roads were partially or fully closed. Ground subsidence had caused potholes at several points in the Naeseong Underpass and the Suyeong Riverside Underpass, prompting emergency repair work. Closures on major arterial roads caused heavy congestion across the Dongnae-gu and Suyeong-gu areas. The Busan city government is looking into whether the ground subsidence near the Naeseong and Suyeong Riverside underpasses is linked to the Mandeok-Centum Urban Expressway, which opened on February 10. Analysts also suggest that approximately 80 millimeters of heavy rainfall across the Busan area the previous day may have weakened the ground near the underpasses, triggering the subsidence.