It happened around 2:15 p.m. Thursday, Sept. 5, in Dix Hills.
A 23-year-old Smithtown man was driving a 2006 Toyota Prius southbound on Deer Park Road at Deforest Road whenthe vehicle struck a northbound 2025 Kenworth semi-truck, according to Suffolk County Police.
The Prius then hit a 2012 Hyundai Sonata that was stopped at a traffic light.
The driver of the Prius was airlifted to Stony Brook University Hospital for treatment of serious injuries.
The driver of the semi-truck, a 53-year-old Dix Hills man, was transported to South Shore University Hospital in Bay Shore for treatment of minor injuries.
The driver of the Hyundai Sonata was not injured.
All three vehicles were impounded for a safety check. Anyone with information is asked to call the Second Squad at 631-854-8252.
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