Animal-control officers removed the raccoon, which will be tested for rabies, and the dog was placed under quarantine and also will be tested, Whitman said.
Authorities do not plan to seek charges against the woman, who heard a commotion in her yard, went outside and saw the raccoon biting her pet's face, Whitman said.
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The woman tried to hit the raccoon with a shovel, but that failed to stop its attack, Whitman said. She then retrieved a revolver and shot the animal, Whitman said.
Police were called to the scene, and officers notified animal-control officers, Whitman said.