Nineteen-year-old Austin Harrouff was dubbed the “face eating” frat boy by the media after being accused of murdering a couple and tearing the flesh off one victim’s face and abdomen with his teeth.

The teen allegedly walked into the garage of the Florida home of John Stevens and his wife, Michelle Mischon, on the night of August 15, 2016 and attacked them with a knife before biting their bodies.

Harrouff’s father, Dr. Wade Harrouff, says he learned of the brutal attack when he received a call from police at 2 a.m.

“Police said, ‘We found Austin.’ I was relieved,” Dr. Harrouff tells Dr. Phil in an exclusive sit-down interview airing Wednesday. He says they informed him his son was in the ICU in the hospital. “The police said, ‘He’s killed two people and eaten them. And the blood that you see is not his own.’”

Dr. Harrouff says he didn’t believe that his son was capable of this type of behavior, as the teen had always been a fun-loving, happy person. “He’s always been the kindest, caring kid I’ve ever seen. He always wanted to help people,” he says.

WATCH: The One Thing Dad Of Florida Frat Boy Accused Of Gruesome Murders Wants People To Know About His Son

However, Dr. Harrouff acknowledges that in the two weeks prior to the murders, his son’s demeanor had changed, and that he did exhibit ‘abnormal’ behavior the night of the attack, including drinking Wesson oil and disappearing from a family dinner.

In the video above, Dr. Harrouff tells Dr. Phil why he believes that his son had been poisoned. And, on Wednesday’s episode, hear what Dr. Harrouff thinks may have caused his son’s behavior, and his message to the families of the victims. Watch more here.