Police in McKeesport, Pa., said the infant, Howard Nicholson, was attacked around 9:30 a.m. and died around two hours later after being flown to Children's Hospital of Pittsburgh, according to WPXI-TV.
The mother, 21-year-old Brandy Furlong, told police that she left Nicholson alone in the living room for mere minutes while she used the restroom Thursday morning, according to the Pittsburgh Post-Gazette. The baby's father, a 26-year-old man whose name has not been released, had already gone to work, and Furlong's two other children, ages 3 and 6, were not at home.
Furlong told police that when she returned from the restroom, she found her son bleeding badly from the head while the family's pet husky -- one of four dogs she had in the house -- hovered above. According to the Pittsburgh Tribune Review, police found blood on the dog's muzzle.
"We knew it was a very, very traumatic injury," McKeesport police Capt. Tim Hanna told the Post-Gazette.
Neighbors told the paper they could hear Furlong screaming into the phone and then ran out to the porch "crying" and "hysterical" while swaddling the baby in a bedsheet.
"It's a terrible tragedy," county police Superintendent Charles Moffatt said, explaining that Furlong often took dogs into her home that she felt had been abused.
Court records show that she was cited last October for failing to have her dogs vaccinated, according to The Post-Gazette.
Ron Filo, a neighbor who saw parademics rushing to save the baby, said the tragedy puts him at a loss for words.
"I just don’t understand how things could have gone so wrong. I just feel so bad for the whole family." Filo told WXPI-TV. "They were so happy to bring him home."
Animal behavior expert Jennifer Shyrock told the Pittsburgh Tribune Review that dogs should never be left alone with newborns, even if they have shown themselves to be the friendliest family pets.
"Whenever a newborn comes into the home, they are unfamiliar to the family dog. This is the biggest risk factor. This is heartbreaking, there's no way around it," Shryock told the paper. "But it is preventable."
CORRECTION: A previous version of this article indicated that the husky was wearing a muzzle at the time of the attack, citing The Pittsburgh Tribune Review. In fact, the paper did not say whether the dog was wearing a muzzle during the attack, only that police found blood on the dog's muzzle. Thanks to Huffington Post commenters for pointing that out.