The father of a Surrey, B.C. toddler, who was savagely attacked by the family pit bull on Friday, says he blames himself for not being more watchful.

"I should have known better,'' said DeJal-Blue Paradis. "I should not have let my son out of my range."

Three-year-old Justice Paradis was rushed to hospital after his family's pit bull suddenly turned on him, biting the boy several times in the face.

While he is expected to survive, the wounds that he sustained in the attack are so severe that he may require plastic surgery, doctors say.

The boy's grandfather, Bill Paradis, told CTV News that the dog belongs to the boy's mother, and it's usually kept on a chain outside the family's house, on 133rd St. in Surrey. The dog, whose name is Haze, hasn't attacked anyone before, he said.

But the boy's father mistakenly let the dog loose inside the house while the children were around at about 2:00 p.m., he said. That's when the dog attacked, biting the father as well as he tried to save the child.

"[The dog] grabbed him on the face and whipped him down,'' said DeJal-Blue Paradis, adding that the boy was left with a hole in his cheek.

The family is now expected to have the dog euthanized.

With a report by CTV British Columbia's Jon Woodward.