Aiden McGrew’s mother Chantel called 911 when she got home around 11am from a doctor’s appointment and discovered the boy’s leg was severed.
The Dorchester County Sheriff’s Office said the boy was attacked and dismembered by a recently rescued retriever.
The dog, who looks to be a golden retriever or some sort of mix, was new to the home, WBTV reported.
Dorchester County Coroner Chris Nisbet said the boy was bitten and dismembered, but he refused to answer additional questions about the infant’s injuries.
He said he hopes an autopsy scheduled for Saturday will determine if the boy was dead before the dog dismembered him, the Associated Press reported.
The attack happened in rural Dorchester County, about 30 miles northwest of Charleston, South Carolina.
Deputies said earlier in the day the boy’s leg had been severed by the retriever. Aiden died at the hospital shortly after he arrived.
‘Today is one of the saddest days in my 20-plus years of being in the Dorchester County Coroner’s Office as I report to all of you one of the worst deaths I have ever handled,’ Mr Nisbet wrote in his email to the media.
Two other children in the home were not hurt, Mr Nisbet said.
A woman answering a number listed for the home refused to talk about what happened and told a reporter to not call her back.
Chantel and Quintin’s two other children, aged three and seven, have been taken into child protective services for the time being, WBTV reported.