Officers of Tokyo Fire Department and a police investigator gather at an entrance of a construction site where a steel frame fell and two male workers died with three others left injured in Tokyo on Sept 19, 2023. (PHOTO / AFP)

TOKYO — Two male construction workers died and three others were injured after steel beams fell at a construction site in downtown Tokyo on Tuesday, according to local authorities.

At around 9:30 am local time, fire and rescue authorities received an emergency call reporting that several workers had fallen from a building under construction in the Nihonbashi area of Tokyo's Chuo district.

A total of 27 emergency response vehicles, including fire trucks, have been mobilized to the scene to conduct rescue operations, according to local media reports

The fallen steel beams, estimated to weigh 15 tonnes, caused four workers to plummet from the seventh floor to the third, while another person was on the third floor when the accident happened, according to the Chuo police station.

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Among the five male workers, two in their 30s and 40s died, and one worker was unconscious and in critical condition, according to the Tokyo Metropolitan Police Department.

Two other male workers in their 20s were also injured but are reported to be conscious, it added.

Earlier during the day, four injured were reported in cardiac arrest.

"I heard a tremendously loud noise, unlike anything I've ever heard before. It sounded like something heavy and metallic had fallen," a shocked restaurant employee near the scene was quoted as saying by national broadcaster NHK.

A total of 27 emergency response vehicles, including fire trucks, have been mobilized to the scene to conduct rescue operations, according to local media reports.

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The accident took place at a construction site of a 51-story building, in close proximity to the bustling JR Tokyo Station Yaesu Exit near a cluster of office buildings.

The mixed-use complex under construction is part of a Tokyo Station front redevelopment project, which commenced in 2021 and is on track for completion in 2025.

The precise cause of the steel beam collapse is still under investigation.