(POSTANDCOURIER) — While his father slept in a nearby bedroom, a 2-month-old boy who had been napping was mauled Friday by the family’s newly adopted dog.

The boy, Aiden McGrew, was apparently pulled from an infant’s swing and his legs torn off by the golden retriever-Labrador mix inside the family’s mobile home on Sandpit Road, authorities said.

Aiden, who was born on Valentine’s Day, was pronounced dead at a hospital.

Neighbors described the dog, named Lucky, as gentle, and they expressed shock. One investigator called the death one of the most gruesome he had seen in his career.

“This is about as bad as it can get for a police officer,” Dorchester County Sheriff L.C. Knight said at an afternoon news conference.

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