The crash, which included a car, an SUV, and a box truck, happened shortly before 7 a.m. Friday near the Northern Westchester/Putnam border.
Three people were cared for and transported to Westchester Medical Center by the Somers Fire Department, the fire department said.
The entire road between Windsor Road and Mahopac Avenue was shut down from about 6:55 to 8:30 a.m., New York State Trooper AJ Hicks said.
Mohegan Lake firefighters also responded to the crash.
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