GRAND RAPIDS (WWJ/AP) – A 911 call from a boy charged in the slaying of a 9-year-old on a western Michigan playground was played during his murder trial Tuesday.

In it, Jamarion Lawhorn, who is now 13, is heard telling a dispatcher to send an officer and that he had “just stabbed someone.” When asked who was stabbed, the boy replied: “I don’t know, I’m fed up with life.”

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The recording followed testimony in Kent County Circuit Court from witnesses and Michael Connor Verkerke’s mother and younger brother.

The victim, called “Connor” by his family, was stabbed to death Aug. 4, 2014, after falling off a slide in Kentwood, near Grand Rapids. The two boys didn’t know each other before the younger boy was approached at the playground.

Lawhorn, who was 12 at the time, is designated as an adult in the juvenile court system. That means he would be sentenced as a juvenile if convicted, then resentenced as an adult at age 21.

Prosecutors said Lawhorn had planned to stab someone for a year and that he hid the kitchen knife used in the slaying in a sandbox and removed his own shirt to keep blood off it.

“He went looking for someone he didn’t know, and that someone turned out to be Connor Verkerke,” Kent County Assistant Prosecutor Kevin Bramble said Tuesday. “His actions clearly show he understood the wrongfulness of his conduct. He knew to call police because he knew it was wrong.”

But defense attorney Charles Boekeloo said in his opening statement that his client was the victim of physical abuse at home. “He had no choice,” Boekeloo said. “This was his only way out.”

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Earlier Tuesday, Dani Verkerke had told the jury that her son introduced Lawhorn as his “new friend” the day of the stabbing.

Lawhorn has been described as behaving “very calmly” after the stabbing. Witnesses said the boy mentioned that he was upset because nobody loved him, and that he had taken multiple pills earlier in the day. After the stabbing, a neighbor told police that the boy said, “I want to die. I don’t want to be on this earth anymore.”

According to a court filing, Lawhorn told investigators he stabbed Verkerke because he wanted to go to jail, that he is “bad and always does stupid things,” and that he thought he’d be killed “for doing something like this.”

The trial is expected to last through at least Thursday.

Lawhorn’s parents have been charged with child abuse, which authorities believe may have contributed to the boy’s mental state, and, in turn, the stabbing. Records showed that he had been living in a volatile home that was described as “deplorable” by child welfare workers.

WWJ is identifying Lawhorn, who turned 12 in March, because he is charged as an adult.

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