CANTON — A maintenance man quietly detailed in court how he lured a 7-year-old girl into a vacant apartment, molested her, beat and stabbed her to death and stuffed her body into a trash bin.

The admission Tuesday as the girl's family sobbed in the front row brought an unusually rapid conclusion to a murder case that frightened a North Georgia community just over a month ago.

Jorelys Rivera disappeared when she left the complex's playground to head to her apartment to get sodas for her friends. Speaking softly and with little emotion, 20-year-old Ryan Brunn, a former Dahlonega resident, told a judge he used her lost roller skate to coax her into the unit in the complex where he had worked for about a month and forced her to undress in a bathtub.

"I didn't want her to go home and tell her mom or dad on me," Brunn said. "So I cut her." Brunn had moved to Canton from Dahlonega just a month before Rivera's death.

Former neighbors had described Brunn as having a troubling past in which police were called to the family's home on several occasions. They also said they had notified police of incidents involving including marijuana use and domestic violence.

But Brian Staples, whose brother is married to Brunn's sister, said Brunn is outgoing and friendly, not the socially awkward, quiet maintenance man who residents at the apartment complex described.

He said Brunn is "into helping people, not hurting people."

A judge swiftly sentenced him to life in prison without parole after making him tell the packed courtroom what happened.

"I would like to apologize for everything I've done," Brunn said, turning to the girl's family. "Lo siento," he said, which means "I'm sorry" in Spanish.

Prosecutors read a statement from the girl's mother, Joselinne Rivera, who said she hopes he suffers as much as her family has.

"The rest of my life I am going to feel terrible and destroyed because of the harm you did to my daughter," Rivera said in the statement. "I desire this man the worst possible of the world, and that they do to him the worst so he suffers."

She and the family didn't comment after the hearing.

The guilty plea to murder, child molestation and other charges spares Brunn from possibly facing the death penalty - and Rivera's family from the prospect of an emotionally devastating trial. Law enforcement officers said the speed of the case even caught them by surprise.

"It's not often that we get to see a monster appear in court and make a full admission. And certainly we don't get to see justice done this fast," said Vernon Keenan, the head of Georgia's Bureau of Investigation. He said Brunn showed at the hearing that he was a "sociopathic killer."

"He has no remorse. And he deserves no sympathy," said Keenan. "He is a cold and calculated killer."

Page Pate, an Atlanta defense attorney who has worked on murder cases, said he was surprised by the speed of the conclusion. Brunn was indicted on the charges just a week ago. He pointed to two possible reasons that led to Brunn's decision.

"The lawyers representing him realized early on they had an uphill battle and I expect they were looking for the fastest resolution possible. Their number one objective was to save him from the death penalty," said Pate.

"And the district attorney's office realized this would be a very costly trial."

Brunn said he chose Rivera after he found her skate outside her apartment building in Canton. He snapped a photo of it and then used it on Dec. 2 to persuade the girl to follow him into a vacant unit he had earlier unlocked.

"I thought to myself, I was going to lure her. I don't know why," he said, adding: "I asked her if it was hers. And she came."

When they got to the apartment, he first forced her to lie on a mattress and undress, he said. When she wanted to use the bathroom, he said he followed her in there and forced her to lie on a bathtub. He said she never asked to leave, but only if she could go home when he was finished. He said he soon grew fearful of the consequences of the assault.

"I got scared in there from what I was doing and I didn't want her to go home and tell on me," he said.

So he bound her arms with plastic ties, stuffed her mouth with a cloth dishrag and then wrapped her face in tape, Brunn said.

He said he then took a razor used for slicing carpet and slit her throat. When she struggled for a few minutes, he said he hit her about five times with the skate and then stuffed her body in a blanket, which he then dumped in a trash compactor.

That night, he said, he helped search for the missing girl for about an hour, went to Walmart with two friends and came home to smoke marijuana and meth. Two days later, though, he said he began "freaking out" as the search for the girl intensified.

He said he took a McDonald's receipt from his car and scrawled a note saying the girl's body was in the trash compactor, which he taped to the device. When pressed by the judge why he did that, he responded simply: "I was high."

Brunn insisted he never had sex with the girl, and prosecutors agreed to reduce charges against him from aggravated child molestation to child molestation. He also pleaded guilty to a range of other charges, including assault and abandonment of a dead body.

He had no history of a criminal past and passed a background check to work at the complex.

Keenan, the GBI director, said after the hearing that investigators uncovered evidence that Brunn had molested other children. He said Brunn's speedy guilty plea gives investigators a chance to delve into Brunn's pathos to uncover what makes him tick.

"If he were on death row, we wouldn't have the opportunity to talk to him and learn and perfect our skills," he said.

Brunn, who is being transferred to state prison, said nothing else as he was escorted from the courtroom, but his attorney offered brief remarks.

"A child's life was lost and he was sentenced," said his attorney, David Cannon. "And that's the bottom line, ladies and gentlemen. It's over."