Jason Dean Bunger, 29, is wanted for questioning after reportedly taking the severely beaten infant to the emergency room at St. Joseph’s hospital on Friday. Jason was questioned by hospital staff, but left before deputies arrived.

20-month-old Zakory Commissaris was severely beaten and left in a coma. He died at a Seattle hospital Sunday after he was taken off life support.

The King County Medical Examiner's Office confirmed the child's death around 11 a.m., Whatcom County Sheriff's Chief Deputy Jeff Parks said.

Bunger was last seen driving a blue 1987 Toyota Camry, with Washington license plate 219-MJV.

An autopsy was planned. The child's aunt, Christina Kuoppala of Bellingham, said doctors at Harborview Medical Center in Seattle told her the cause of death was a blow to the back of the head.

Investigators believe Bunger brought the unconscious toddler to the emergency room at St. Joseph Hospital in Bellingham on Friday afternoon. That night, the boy was flown to Harborview Medical Center in Seattle with "life-threatening" injuries and bruises over parts of his body, said Sgt. Steve Cooley.

"All the police said is that my nephew was tortured," said Kuoppala. "He had cuts from head to toe."

Kuoppala said Zakory's parents were in the middle of a move and were staying at a small motel, so they sent the toddler to spend a few days with the 29-year-old family friend.

That friend took the boy to St. Joseph's and told nurses the child had fallen out of bed.

Hospital staff questioned Bunger, who said the boy had been staying with his family for about a week while his parents were away. He left before deputies arrived.

Deputies served a search warrant at the man's home, and questioned several people, including his girlfriend, the boy's parents and other family members.

A second child belonging to the man and his girlfriend was placed with Child Protective Services.

"This monster that did this to him is gonna pay," said Kuoppala while fighting back tears. "You can't do this to a child and get away with it."