HESPERIA, Calif. (AP) — A 4-year-old Southern California boy who was bitten by his father’s police dog has lost part of his leg.

Hunter Mastaler remains hospitalized Thursday following surgery and is expected to recover.

Mastaler’s father is a canine handler with the Rialto Police Department. Police Capt. Randy De Anda says the 7-year-old Belgian Malinois named Jango was in the backyard of the family’s Hesperia home Sunday when the boy went outside. The dog bit and held onto the boy’s left leg as it is trained to do in criminal situations.

Neighbors heard the boy’s screams and helped rescue him.

De Anda says the dog has an impeccable service record and it’s unclear why he attacked. Jango is quarantined for now, but De Anda says it’s likely he’ll be destroyed.

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