The two-car crash occurred at the intersection of Route 202 and Summer Road in Readington Township just after 6 p.m., the Flemington-Raritan First Aid and Rescue Squad said.
The Whitehouse Rescue Squad also responded and worked alongside the FRFARS to quickly extricate one of the victims, a 19-year-old man, who was then taken via NJSP NorthSTAR medical helicopter to Robert Wood Johnson University Hospital trauma center in New Brunswick.
A second victim was taken by ground ambulance to RWJUH, and a third occupant refused medical attention, authorities said.
The crash scene was cleared in about 90 minutes, FRFARS said.
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Other assisting agencies include the Three Bridges Fire Company, which set up a landing zone at Summer Road Park, and RWJ Paramedics.
The crash remained under investigation by the Readington Township Police Department.
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