An Auburn, New York police officer shot a dog once as he charged the officer. The dog had been running loose (apparently common for this dog). The dog nipped one child and attacked a smaller dog. When cornered, the dog charged the officer and, given the fact the dog had exhibited willingness to use teeth on skin, the officer shot at the dog. One shot - the bullet hit the dog in the leg and traveled through the chest. Animal control officers were able to subdue the dog with pepper spray and a catch pole. At the vet, the dog was euthanized.
ETA: The original article calls the dog a pit bull. The sister of the owner disputes that, saying the dog is actually a boxer/blue heeler mix. Fascinating confusion.
Also, the updated article states that the officer attempted to use a baton to subdue the dog before shooting him.