The teen was working in the warehouse assembling shelving when he fell 15 feet about 3 p.m. on Saturday, according to South Brunswick police.
Police did not disclose the teenager's name or the company he was working for,
Paramedics with Monmouth Junction First Aid Squad took the teen to Robert Wood Johnson University Hospital.
Federal officials with the Occupational Safety and Health Administration (OSHA) are investigating the workplace accident.
The teenager remained in critical condition on Monday, police said.
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