Atlanta (CNN) -- Ryan Brunn, the man who this week was sentenced to life in prison after pleading guilty to murdering a Georgia girl, apparently killed himself in his prison cell Thursday, a corrections spokeswoman said.
Georgia Department of Corrections spokeswoman Kristen Stancil said that Brunn was found unresponsive at 4:15 p.m. in his cell at Georgia Diagnostic and Classification Prison in Jackson. Brunn was pronounced dead at a hospital at 5:37 p.m. due to an apparent suicide, she said.
The case since has been referred to the Georgia Bureau of Investigation, according to Stancil.
Brunn had entered a guilty plea Tuesday at a hearing in a Cherokee County courthouse, during which he described in detail how he enticed, molested and killed 7-year-old Jorelys Rivera. He was subsequently sentenced to life in prison without the chance of parole, avoiding a potential death sentence by lethal injection.
The girl's father, Ricardo Galarza, told CNN en Espanol that news of Brunn's death partly made him "feel good but, on the other hand, it doesn't because my daughter will never be with me again."
Galarza said that he felt that a lifetime of Brunn being watched after, "eating three times a day (and) sleeping with air conditioning" while in prison was not enough.
"What I wanted was for them to put him in the electric chair and burn him," the father said. "I would have taken him there myself and prepared it, so he would burn."
Jorelys' mangled body was found in a trash compactor three days after she went missing on December 2 from an apartment complex in Canton, about 40 miles north of Atlanta.
According to the indictment, Jorelys was severely beaten and stabbed repeatedly in the face, neck and chest.
Brunn, 20, who worked as a maintenance man at the same apartment complex, was arrested on December 7 and charged with the crime.
Last week, Brunn was indicted on 13 counts including murder, aggravated assault, cruelty to children, aggravated child molestation, enticing a child for indecent purposes, false imprisonment, abandonment of a dead body, making a false statement and sexual exploitation of children.
He told the court Tuesday that he had never talked to Jorelys before the day of her murder. He said he devised a plan after he found one of her skates.
Brunn took a picture of the skate and approached her with it, asking if the skate was hers. She said yes, and Brunn promised to take her to it.
Instead, he took her to an empty apartment and instructed Jorelys to pull down her pants. He then put tape over her face and cut her throat with a razor. At this point, she was still alive, he told the court.
He said that he then took Jorelys to the bathroom and beat her to death with the skate. He said he did not have sex with the girl.
Increasingly, Brunn told the court, he grew concerned about what he had done. So he took a receipt, wrote on the back of it, "She is in the trash can," and taped it to the compactor.
He admitted lying to investigators who had questioned him about the case. Brunn said he knew right from wrong, adding he "never had an idea of killing a child in my life."
"I'd like to apologize for everything I've done, and I do deserve everything that you're about to give me," he said in court.