The accident, reported at 4:30 p.m., occurred on the westbound side near Windsor Road, just west of Mahopac Avenue.
Motorists should avoid Route 6 between Mahopac Avenue and Curry Street for at least the next two hours, Yorktown Police said.
If taking the Taconic State Parkway, Yorktown Police advise motorists to take the Bryant Pond Road exit as an alternate.
Expect heavy delays on Route 6N as well as East Main Street in Jefferson Valley.
Farther north, an accident is causing delays in Dutchess at Route 55 in LaGrange near the Taconic State Parkway.
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