On May 31, 2025, police in Seoul apprehended a man in his 60s after a suspected arson attack on a Line 5 subway train forced hundreds of passengers to evacuate through a tunnel. Yonhap said the fire broke out between Yeouinaru and Mapo stations at 8:47 a.m., and that the suspect was taken into custody near Yeouinaru Station at 9:45 a.m. after being on the run.
The incident quickly became a major transit emergency because of where and how it happened. According to the report, the suspect boarded the train carrying a lighter-type torch and a fuel container, then allegedly set fire to pieces of clothing inside the carriage. That combination suggests the attack was prepared rather than improvised, which helps explain why the fire spread into a situation that threatened dozens of passengers at once.
More than 400 passengers escaped through the tunnel, and 21 of them were sent to hospital for injuries including smoke inhalation and a fractured ankle. Yonhap said no serious injuries had been reported so far. That is an important distinction. A subway fire of this size could have become much worse, and the fact that the injuries were not more severe does not reduce the seriousness of the evacuation itself.
Passengers and the train conductor initially used fire extinguishers to contain the flames before they were fully extinguished at about 10:24 a.m. Authorities then dispatched 230 personnel, including firefighters and police officers, to the scene. Subway service between Yeouido and Aeogae stations was suspended for a while before resuming at 10:06 a.m., showing how quickly one violent act can ripple through a city's transport system.
The report said police plan to question the suspect about motive and conduct a forensic examination of the scene. That is likely to determine whether the attack was driven by personal grievance, mental distress or something else entirely. What is already clear is the operational impact: a morning commute turned into a tunnel evacuation, a medical response and a transit shutdown.
Seoul's subway system is usually a symbol of routine precision. On this morning, it became the site of a dangerous break in that routine, one that required passengers, staff and emergency crews to improvise under pressure until order was restored.
Incidents like this also test public confidence in mass transit. A subway system depends on passengers believing that a normal commute will stay normal, so when one train turns into a smoke-filled evacuation, the shock travels beyond the platform. The response described by Yonhap suggests the system and emergency services contained the danger quickly, but the motive question remains central because motive determines whether the attack was personal, political or something else entirely. For the city, the operational success of the response will matter, but so will the legal follow-up if investigators conclude the suspect acted with intent.
Even without serious injuries, the fire is the sort of event that can leave a long shadow over how people use the system the next morning. The transit response may have been fast, but the memory of the evacuation will linger.
