NEW YORK (CBSNewYork) — Investigators are trying to figure out what caused a construction accident in the Bronx on Tuesday left one worker dead and two others seriously injured.

Devastated family members reacted to the news of a collapse in a building at 94 E. 208th St. in the Norwood section of the borough, CBS2’s Dick Brennan reported.

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Firefighters said part of the structure came crashing down on workers just before noon, crushing one man to death, and seriously injuring two others.

“It appears they were working on the second floor in some sort of collapse. They were trapped in material from the third floor to the second floor,” FDNY Chief John Esposito said.

The Department of Buildings investigators were on the scene Tuesday afternoon. City records show that workers were building a new four-story residential building with eight units.

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“The firefighters had to put up ladders and access the second floor. There was a lot of rubble, a lot of broken concrete blocks, a lot of the building material that covered the area. We had to dig through it to locate the missing worker,” Esposito said.

Three other people suffered non life-threatening injuries. Firefighters said it was treacherous for them completing the rescues because they were worried about the potential for another collapse.

“We had serious concern for our firefighters and the other workers at the scene about the second floor collapsing onto the first floor. We were able to build shores and put struts in there to support that load, to make it safe for the rescue effort,” Esposito said.

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CBS2 reached out to the construction company, Pioneer Contracting, but it did not respond. The superintendent of the site, Linzi Construction, would only say it was headed to the scene and had no comment.