The incident took place around 7 a.m., Wednesday, Dec. 11 on Route 25 near the Calverton Cemetery in Riverhead, said the SPCA on Facebook.
The vehicle -- a dark-colored SUV -- was observed heading eastbound. A witness said they saw a person throw an 8-week-old pitbull mix out of the moving SUV.
The first three letters of the vehicle's license plate are TZR, the SPCA said.
The puppy treated at an animal hospital in Riverhead and is expected to survive.
If you recognize the dog or have any information on the vehicle or driver, contact the Suffolk County SPCA at 631-372-7722.
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