Antonio Barbeau and Nathan Paape -- both 13 years old -- are charged as adults with first-degree intentional homicide.

In Sheboygan County court, state agents and police detailed their chilling interviews with the eighth-grade boys in the days following the killing.

Barbara Olson, 78, was found dead in her garage two days after she was robbed and killed.

The defense claims the boys never intended to kill and only meant to scare her.

The teens walked into the courtroom for their preliminary hearing looking straight forward and showing no emotion.

The boys are accused of killing Olson by striking her several times with a hammer and hatchet, then driving off in her car with a few hundred dollars and jewelry that they used to eat pizza and buy marijuana.

"Basically, they said they were freaking out and the window shades to the living room were open, and they shut them, and then talked for a few hours of what they should do next," said a special agent with the Division of Criminal Investigation.

Another DCI special agent, Lisa Wilson, also testified about their interviews with the boys.

The agents said each boy accused the other of killing Olson.

Wilson said when she asked Paape about the details of how Olson died he became upset.

"During the initial part he was answering our questions, at other times he would look down at the floor, his leg was shaking once we began talking about the incident specifically involving Barbara Olson. He was crying," says Lisa Wilson, also a special agent with the Division of Criminal of Investigation.

The agents testified that the boys were dropped off by Paape's mother near Olson's home and had masks or bags in an attempt to cover their faces and hide their identities, but never used them when they walked in the door.

Prosecutors want the boys charged as adults and feel confident Tuesday's testimonies by the detectives will ensure that happens.

"Yeah, they look 13, but as a prosecutor you don't look at their Justin Bieber haircuts or their innocent faces, you look at what they did, whether they're 13 or their 80, I think all prosecutors look at people, you are how you act," Sheboygan County district attorney Joe DeCecco said.

Defense attorneys said the boys are not mentally mature enough to be tried as adults.

"The frontal lobe of the brain, that reasoning, judgment, or what we would collectively call maturity resides, and that that part of the brain doesn't fully develop until early or mid-20," Barbeau's attorney, George Limbeck, said.

The boys will be in court next month. Their attorneys said they will try to get the case sent to juvenile court

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