A newborn baby was fatally attacked by the family’s dog in their Mira Mesa home last Friday [April 22] in San Diego.

The home was investigated after the parents reported to authorities the fatal accident by their mixed breed American Staffordshire Terrier. According to police, the family was watching television in bed when the mother coughed, startling the dog who then bit the infant.

The couple took the severely injured baby to Thornton Hospital, where he was pronounced dead. The San Diego Police Department believes everything about the incident is nothing more than a tragic case of an accident.

The two-year-old dog named Polo was taken by the county Department of Animal Services and will be quarantined for 10-days to ensure he’s not rabid. The pet had no known prior history of aggressiveness but if not reclaimed by the owners the dog will then be euthanized, authorities said.