Authorities said the attack happened on Terrace Court in Albertson around 1:15 p.m.
Police said a 70-year-old woman was discovered by her 66-year-old husband, mauled, mutilated and being dragged through the backyard of their home by the family pit bull.
Police responded and fatally shot the 7-year-old dog. The woman was pronounced dead at the scene.
Nassau County Police Commissioner Patrick Ryder said the officer who shot the dog was traumatized and is currently being treated at the hospital.
We're told the dog had belonged to the victim's step-son, who died in a motorcycle accident.
Police say they don't know why the dog turned on the woman.
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