A pit bull bit and seriously injured a 5-year-old boy Friday in West Valley City.

The dog bit the boy on the face and head, said West Valley City police Lt. Dalan Taylor. A helicopter flew the boy to Primary Children's Medical Center.

The "attack," as Taylor called it, happened about 5 p.m. near 3000 S. Ray St. (4175 West). The boy lives across the street from the dog's owner and both the 5-year-old and the animal were on the street a few houses down.

Taylor said police had not yet found a witness to the attack and do not know what, if anything, spurred the dog to bite. The dog's owner said the dog was in a kennel and on a leash in a fenced yard when he left for work in the morning and does not know how the dog got loose.

Animal control officers took possession of the dog and are investigating the case. Taylor said no citations have been issued.

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