BUENOS AIRES — 2012 · Major Tragedy

The Once Train Disaster

SolvedSources: ALast updated: 14 October 2026

On the morning of 22 February 2012, in the rush hour of the first working day after the Carnival holiday, an eight-carriage commuter train on the Sarmiento line carrying about 1,000 passengers hit the buffers as it entered Buenos Aires's Once station. Arriving at 26 km/h, its front carriages telescoped; 51 people were killed and more than 700 injured. The dead and seriously injured were in the first two carriages, crowded with passengers who had moved forward to be near the exit. Maintenance failures by the private operator and the state's failure to supervise it became the focus of the investigation. In December 2015, 21 people were convicted, including one of the operating company's owners and a former transport secretary. The disaster became a symbol of corruption in Argentine public services.

Date: 2012
Place: Balvanera, Argentina, Buenos Aires, AR
Category: Major Tragedy
Case Status: Solved
Coordinates: -34.6090, -58.4060 ↗

Timeline of Events

22 February 2012The train hit the buffers at Once station; 51 people died.
2012The investigation focused on failures of maintenance and oversight.

29 December 2015Twenty-one defendants were convicted and seven acquitted.
March 2018The courts upheld the experts' findings on the state of the brakes.

Sources

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