SEOUL, South Korea — A routine infrastructure project turned catastrophic in central Seoul on Tuesday afternoon when a massive section of an aging overpass collapsed during demolition preparations, killing three people and injuring three others. The disaster has triggered a suspension of vital rail lines and sparked intense public scrutiny over safety protocol failures.

The incident occurred on Tuesday, May 26, 2026 at approximately 2:32 p.m. at the Seosomun Overpass demolition site located in Migeun-dong within the city’s Seodaemun District.

The tragedy unfolded while engineers and site managers were conducting an emergency safety inspection. Demolition work on the 60-year-old overpass had actually been halted earlier in the day after workers noticed a structural defect—a slight sagging and a 2.9-centimeter subsidence gap in the concrete slab following cutting operations.

A team of experts and managers walked into the site to evaluate the danger. Minutes later, a major support girder and an upper deck slab suddenly failed, caving in completely and burying the personnel under tons of concrete wreckage and scaffolding.

Among the 12 workers present at the site, three men—the construction site manager, a senior engineering supervisor, and an outside safety inspector—were crushed and killed. Three other workers sustained serious injuries to their heads, ribs, and backs and were rushed to nearby hospitals. The remaining seven managed to evacuate safely.

"As soon as I heard a loud bang, dust came pouring into my store," said Kim Chang-tae, a local shop owner who witnessed the immediate aftermath. "I heard faint moaning—people crying for help—so I immediately called the fire department."

Fire authorities arriving on the scene quickly issued a Level 1 emergency response, deploying dozens of rescue personnel alongside specialized equipment to look for additional casualties trapped in the heavy debris.

Because the Seosomun Overpass spans directly over a critical rail corridor used by major commuter lines and the KTX high-speed train networks, the falling debris struck the tracks and took out overhead power lines. The Korea Railroad Corporation (KORAIL) immediately announced emergency service modifications and suspensions, including halting all train services between Seoul Station and the Haengsin train depot.

Built in 1966, the 335-meter-long Seosomun Overpass had a long history of structural concerns. It was closed for demolition after receiving a deficient "D" safety rating in recent years. The teardown project began last year and was just weeks away from its scheduled completion.

In the wake of the incident, engineering experts have labeled the collapse a "100% man-made disaster," questioning why personnel were sent onto the compromised structure to inspect it without adequate temporary reinforcements or strict safety bracing already in place.

President Lee Jae Myung expressed profound condolences to the victims' families and issued a swift directive, ordering Labor Minister Kim Young-hoon to enforce an immediate stop-work order on the site and mandating a thorough investigation into the cause of the disaster. Both major candidates for Seoul mayor paused their current political campaigns to visit the scene as the city administration transitions into emergency management mode.