The woman, whose name has not been released pending family notification, was walking on the westbound shoulder on East Main Street when she was struck by a vehicle that fled the scene, according to Lt. Richard Malan.
The woman was taken to Hudson Valley Hospital Center in Cortlandt where she was pronounced dead, according to Malan.
"It is possible that the person who struck the victim may not be aware they struck a person," Malan said.
Malan is appealing for the person to come forward and said their car would have a damaged right front headlamp and fender.
Yorktown Police are investigating the incident with assistance from the Westchester County Department of Public Safety's Crime Scene Unit.
Anyone with information is asked to call Yorktown Police at 914-962-4141 or or the detective division at 914-962-3856.
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