The girl has a fractured skull and multiple lacerations to her head and face, said Shawn Vaughn, spokesman for the Texarkana, Texas, Police Department.
Officers were dispatched at 6:30 p.m. Tuesday to a call of a child being attacked by a dog at a residence at 1604 West 21st Street, Vaughn said.
A person who called for help told police the toddler wasn't breathing.
When officers arrived, they were directed to the back yard where a pit bull dog had the girl's head in its mouth.
Fearing for the child's safety, one of the officers was forced to shoot the dog three times.
CHRISTUS St. Michael Hospital and later air lifted to Arkansas Children's Hospital.
The dog, which died at the scene, was a family pet and was chained in the yard when it attacked the child. The dog's body is being taken to the Texas Department of State Health Services in Austin for testing, Vaughn said.
Detectives continue to investigate the incident.
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