ANDERSON, S.C. – Jesse Osborne, the teenager accused in the 2016 shooting at a South Carolina elementary school, pleaded guilty to murder charges Wednesday.

The lead prosecutor in the case said he will seek life imprisonment for the 16-year-old boy.

Osborne pleaded guilty to killing his father, 47-year-old Jeffrey Osborne, at their home, and a 6-year-old boy, Jacob Hall, at Townville Elementary School. He also pleaded guilty to three counts of attempted murder related to trying to kill two other students and a first-grade teacher on the school playground on Sept. 28, 2016.

During Wednesday's hearing in the Anderson County Courthouse, David Wagner, who is prosecuting the case, read from online messages attributed to the Osborne. Wagner said Osborne planned the attack and said that he hoped to kill at least "50 or 60" people at the school.

Investigators say Osborne killed his father in their home before driving his father's truck 3 miles to the school, where the teen opened fire on the playground and mortally wounded Jacob, a first-grader who died three days later.

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Osborne had turned 14 a few weeks before the shooting. Photos taken inside his home offer a glimpse of what once was his teenage existence. His bedroom contained electronics, multiple gaming systems and dozens of video games, including multiple versions of the game "Call of Duty." Assistant Solicitor Catherine Huey, one of the prosecutors connected to this case, would later say Osborne had "lots of shooting games."

Family Court Judge Edgar Long determined last February that Jesse Osborne should be tried as an adult. At an arraignment in September, the teen, through his lawyer, pleaded not guilty to murder charges.

Osborne repeatedly said "Yes, sir" Wednesday as Judge Lawton McIntosh asked him if he understood that he was pleading guilty and if he understood what that meant.

Osborne faces a minimum sentence of 30 years in prison and maximum of life imprisonment.

Because of his age at the time of the crime, and because he could face life in prison, state law requires a special hearing before he is sentenced. At that hearing, a judge will consider things that include psychological evaluations of Osborne, his family life and home environment, and whether he can be rehabilitated.

Wagner said that hearing will likely happen in late spring or early summer.

Osborne's lead attorney, Frank Eppes, said that in the two years he has known and worked with the teen, "He has always been remorseful for his crimes and has always understood he needs to pay for his crimes."

He said that Osborne is "guarded, as many teenagers are," and that he rarely speaks about the events of that day.

"He is in a regulated, structured environment, and that has been good for him," Eppes said after the hearing. "At the end of the day, he's still a kid. He's a child."

Wagner said he is seeking life imprisonment for Osborne because it is the "appropriate sentence for the murder of a 6-year-old Jacob Hall, and the attempted murders of his classmates and teachers.”

Records and testimony presented in Osborne's waiver hearing in February showed that he had plotted the Townville school shooting for months and had refined his plan in the days prior to the shooting. Instagram messages from an account attributed to the teen showed he had studied law-enforcement response times.

Court records also showed the teen Googled "youngest mass murderer" and searched for information on Columbine High School killers Eric Harris and Dylan Klebold.

Osborne, who met with investigators alone after the shootings, confessed to them. Eppes unsuccessfully tried to get that confession thrown out of court earlier this year.

The video footage of Jesse Osborne's confession was played in court in February.

Osborne shot his father three times in their Townville home, then put on a vest he wore when playing with AirSoft guns, he said during his interview. Then he "hugged all the animals" before leaving his house in his father's truck to drive to the school, he said.

Osborne told FBI Special Agent Aleta Bollinger and Tracy Call, an investigator at the Anderson County Sheriff's Office, that he used his father's gun while firing on the playground.

He said he would have killed more at the school but the gun jammed.

Jacob's father, Rodger Hall, sat with his head in his hands at points during Wednesday's hearing. Some family members next to him sobbed.

Jacob's mother, Renae Hall, is in jail and did not attend the hearing.

Renae Hall has had an especially troubled time since her son's death and has been arrested multiple times in the last two years. She has multiple pending drug charges against her, including one from less than a month ago, according to court records.

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