Michael Williams, 61, says he was spraying for bugs outside his house on the 9500 block of Goodwin Street on Monday evening when he heard his neighbor call for help.
Williams said he saw his neighbor "screaming, terrified" and waving what he described as a scarf to ward off a pit bull that was attacking her.
As he stood between her and the dog, Williams said a gun that was in his left hand was discharged and hit the 53-year-old woman.
The Wayne County Medical Examiner identified her as Patricia Crosby and ruled the death a homicide. She died of a gunshot wound to the left flank, according to the medical examiner.
Williams, who said he patrols the neighborhood in his car to protect children, says he wasn't aiming and doesn't know how the bullet hit his neighbor, who was taken to a hospital, where she died.
"What's going through my mind is, I hate I was there and don't hate I was there," Williams said. "It just hurts when you're trying to help somebody and then they get hurt, trying to save their life."
After his neighbor was shot, Williams said he carried her to her porch and then went after the dog, firing about two shots but failed to hit it. He described the dog as a beige or tan color pit bull that was mean in temperament.
"The dog was like hungry," Williams said.
He couldn't remember if his neighbor had been bitten and said that he didn't suffer any injuries from the dog.
Officers who responded to the scene were not able to immediately locate the dog.
Williams said he was detained for about two hours and taken to police headquarters.
"They treated me with respect," Williams said of the police. "I was scared."
Authorities are investigating the incident.
"The gentleman who shot the woman is very cooperative and he is not in custody but the investigation is still open and will continue. After it is complete, a warrant packet will be submitted to the prosecutor's office just like any other case," said Officer Jennifer Moreno, a Detroit police spokeswoman.
Moreno said the department does not know who the dog belonged to but believes it ran off after the shooting.
"It is unknown if the dog was shot or not," she said.
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