A 2004 Audi struck the 57-year-old officer around 11:35 on Tuesday morning, authorities said. The 29-year veteran was conducting a checkpoint on Route 878 at the time.
He sustained multiple injuries, including a fractured skull, fractured pelvis, fractured right leg and massive internal bleeding. He was airlifted to a local hospital by the Nassau County Police Aviation Unit.
He underwent surgery and remains in critical condition.
A 43-year-old man was behind the wheel of the Audi, police said. A 20-year-old woman and 9-year-old boy were passengers in the Audi, but no one in that vehicle was hurt.
The driver stayed at the scene and is not expected to be charged.
The investigation is ongoing, and the Audi was impounded for a safety inspection.
No names were released.
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