AUSTIN (KXAN) — An affidavit revealed more details in a police investigation for a man facing a murder charge related to the death of his father.

According to a murder affidavit for 31-year-old Jesse Anthony Rivera, police responded to a 911 call at approximately 8:15 p.m. April 13 in the 10900 block of Mickelson Drive after a man reported he had “just killed someone that wasn’t his dad.”

Officers arrived at the home a short time later, and Rivera left the residence while still on the phone with the 911 call taker.

During a police interview with Rivera, he said the victim had become a different person in the past couple of weeks and had become more aggressive with him. When asked to clarify what he meant by more aggressive, Rivera said the victim would not respond to him when he tried to have conversations with him and instead would ignore him.

When asked what happened that night, Rivera said the victim walked by him and gave him a weird look that made him feel like he “had to do because that wasn’t his father.” When asked what he meant by that, Rivera told police he said “do what I have to do,” the affidavit states.

The affidavit said Rivera admitted to police to hitting his father in the head with a baseball bat several times and then stabbing him with a kitchen knife, which ultimately caused his death.

An autopsy report showed that Rivera’s father, Jesse Anthony Rivera Jr., sustained sharp force trauma and blunt force trauma tohis head and neck, and the manner of death was homicide.