The incident occurred at a new home under construction on South Bayview Avenue in Freeport just before 2 p.m. Monday, July 1.
The teen, 18, has been identified as Alberto Mejia-Montoya of Hempstead, Nassau County Police said on Tuesday, July 2.
According to detectives, officers were called to the construction site for a report of two injured workers.
While working at the site, both men were standing on a scaffold that broke, Nassau County Police said. Mejia-Montoya suffered a skull fracture, sustaining multiple life-threatening injuries.
The second victim, 30, suffered a minor injury to his shoulder. Both were transported to South Nassau Hospital.
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