CORAOPOLIS, Pa. -- Police said a 5-year-old Pittsburgh-area boy is in critical but stable condition after his face was mauled by a pit bull.

The dog has been quarantined by police in Corapolis who are not identifying the boy or his aunt, who was watching him at the time at a home along Birch Way.

Police said the boy was attacked at about 5 p.m. Wednesday when he went into the back yard to feed the dog, which was tied up. Police don't know why the animal, which weighs about 70 pounds, attacked the boy.

Channel 11's Timyka Artist spoke to a neighbor who drove the child and his mother to the hospital. The neighbor said the boy had several cuts on his face and chin.

The dog's owner wasn't home at the time and police are not releasing his name. No charges have been filed against him.

Police said the 10-year-old dog, named "Stiff," was docile when Triangle Pet animal control officers took him away.