CANANDAIGUA — A city police officer shot and killed a pit bull that had attacked its owner and then charged at the officer, police said Friday night.

According to police, officers responded to the report of a dog attacking a woman on Saltonstall Street shortly after 5 p.m. When the arriving officer ran toward the scene to help the woman, the dog released the woman’s arm and charged at the officer, police said.

The officer subsequently fired three rounds from his gun, killing the dog at the scene, according to police.

The woman attacked by the dog was identified as a 29-year-old Canandaigua resident who was the dog’s owner. Police said she was taken to Strong Memorial Hospital in Rochester by Canandaigua Ambulance with severe injuries and disfigurement to her right arm and hand, and bite injuries to her right leg, left shoulder, and her face.

Police said it appears the dog attacked the woman while she was walking it on a leash, and that the dog had also attacked a bystander who attempted to approach the scene and help the woman prior to the police arriving.

They said the bystander suffered multiple minor injuries, but declined treatment at the scene.

Police said the Ontario County Humane Society was notified and responded to take custody of the deceased animal.

Canandaigua police said they are continuing to investigate the history and origins of the dog.