A pit bull mauled to death a 6-year-old boy who apparently had climbed over a 4-foot chain-link fence to get into a neighbor's yard in western North Carolina, authorities said Wednesday.

The Henderson County Sheriff's Office was called to a residence in Hendersonville, south of Asheville, on Tuesday and found the boy, Joshua Phillip Strother, lying unresponsive in the fenced backyard. The 1-year-old male pit bull there was so aggressive officers had to shoot and kill the dog so emergency workers could get to the child, sheriff's office spokesman Maj. Frank Stout said.

Resuscitation efforts were unsuccessful, and the boy died at the scene from wounds to his head and neck, Stout said.

"The child appeared to have died a very violent and quick death," Stout said.

The boy's mother, Amanda Strother, called 911 at 4:17 p.m. Tuesday and told the dispatcher she had gone to the bathroom and lost sight of the boy for five to 10 minutes and then was unable to get into the neighbor's yard where he had been attacked.

"I was in the house and I heard the back door shut, and I come running and I see him lying in the neighbor's yard," the mother told the dispatcher, according to the 911 recording of the conversation.

Weeping, she said there was blood on the boy's face and he didn't appear to be breathing. He did not respond when she called his name and the neighbors were not home, she said.

After Animal Enforcement officers shot the dog, officers had to push down the chain-link fence to access the victim, Stout said.

Strother told the emergency dispatcher that her son and other children routinely climbed over the fence and had played with the dog in the past. Strother's cousin Kathy Etheridge said Joshua was "just a sweet little blond-headed boy who loved to play outside."

The neighbors adopted the dog from an animal shelter about three weeks ago, Stout said. The sheriff's office is investigating the unnamed shelter and the dog's history to discover whether the animal has ever been deemed dangerous.