The incident happened around 2:30 p.m. Thursday, July 18, in North Hills.
A 43-year-old man was at Christopher Morley Park, located at 500 Searingtown Road, with his Belgian Dutch Shepherd when it turned on his owner and began to viciously attack him.
Fearing for his life, the man fired one round at the dog.
The canine, who was off his leash at the time of the incident, succumbed to its injury.
The man, who police say has a licensed pistol permit, suffered lacerations to his left arm and left leg. He was transported to a nearby hospital for treatment and evaluation.
There were no other injuries reported.
The investigation is ongoing.
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