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San Diego police Sgt. Tu Nguyen, who works with the department's child abuse unit, told the Los Angeles Times that the mauling happened at 8 p.m. Thursday in San Diego.

The parents were on the bed watching TV with their 3-day-old son and their dog, a 2-year-old neutered male American Staffordshire terrier-mix named Polo.

Nguyen said the dog was startled when the mother coughed and attacked the newborn.

He said the parents pulled the dog off of their son and took him to the hospital.

The newborn was pronounced dead at the hospital.

"At this time, we're looking at this as nothing more than a tragic incident," Nguyen said.

Polo was taken into custody of the county Department of Animal Services, where Deputy Director Dan DeSousa said he will remain quarantined for 10 days to determine if he has rabies.

DeSousa said the owners will decide if they want to reclaim the dog.

"It’s such a horrific, tragic incident they are going through," Nguyen said.