SAN DIEGO (AP) — A 3-day-old boy mauled to death by the family dog died from bites to his head, according to autopsy results released Monday.

The autopsy, released by San Diego County’s medical examiner, also ruled the death of Sebastian Caban an accident.

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San Diego police say the newborn was in bed with his parents and the dog Thursday night when the mother coughed, startling the animal and prompting the attack.

The couple pulled the dog off the baby and made two unsuccessful 911 calls before getting frustrated and taking him to the hospital themselves, police said. The baby was pronounced dead at the hospital after efforts to revive him were unsuccessful, according to the autopsy.

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The parents waited 28 seconds before hanging up their first call to 911, then tried again and waited 34 seconds before giving up, police Lt. Scott Wahl told KNSD-TV on Saturday.

Police said the family has their condolences and that they’re also frustrated by slow 911 response times. They said their operators are understaffed and that 73 calls came in during the half-hour span when the parents called.

The 2-year-old dog is a neutered male American Staffordshire terrier-mix named Polo. He’ll be held in quarantine for 10 days before the owners must decide whether to reclaim him.

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