Fire authorities are seen at the site where part of the Seosomun overpass collapsed during a demolition project in Seodaemun-gu, Seoul, on Tuesday. (Yonhap) At least six people were trapped or injured Tuesday after part of an overpass under demolition collapsed in western Seoul, prompting emergency rescue operations and disrupting train services in the area, authorities said.The accident was reported at around 2:32 p.m. at the Seosomun overpass demolition site at 317-1 Migeun-dong, Seodaemun-gu, according to fire authorities and Seoul city officials.Authorities said part of the road deck collapsed during demolition work, leaving one demolition vehicle and an estimated six people trapped beneath the structure.The first fire crew arrived at the scene at around 2:38 p.m., six minutes after the report was received. Fire authorities issued a Level 1 emergency response at around 2:49 p.m., mobilizing 62 personnel and 16 vehicles to the site.Five additional ambulances were also dispatched, while about 30 police officers were sent to the scene.Emergency officials relayed safety precautions to field responders at around 2:42 p.m. and reported the situation by phone to the National Crisis Management Center and other relevant authorities.Korail said train operations between Seoul Station and Sinchon Station had been suspended following the collapse, affecting the Gyeongui Line and other nearby services.Authorities have yet to determine the exact cause of the accident.