A family has been left in shock after a newborn baby has been mauled to death by the family's dog.

12-day-old Elon was attacked in Doncaster, northern England by a chow chow cross.

The baby suffered from serious injuries and was taken to the hospital but later died.

The family had celebrated the birth of Elon by posting pictures on Facebook, with mother Abigail and father Stephen commenting “Our gorgeous baby boy. Love him to bits”.

The couple were arrested on suspicion of gross negligence manslaughter after the attack, but have both been released on bail.

The baby's uncle said that the baby had been lying in his bassinette when the dog ran inside after escaping from a pen in the yard.

The father and uncle tried to save the baby, but to no avail.

“It was horrible and we’re all in total shock,” the uncle said.

“My sister is in bits. She’s lost her baby.

“Teddy’s not a dangerous dog... I think he was jealous when the baby came along.

“Or maybe he thought the baby was a toy – he was a tiny thing.”

One of Abigail's closest friends said that the mum was a "brilliant" parent.

“She loves dogs and would never have a dog around the kids if she thought they were dangerous,” the friend said.

Ellis' other three children were at the house at the time of the attack.

The dog has been removed from the home as investigations continue.

Photo credits: 7News