A 12-year-old boy was charged with murder after stabbing a 9-year-old boy in the back at a Michigan playground, authorities say. 

The Associated Press reports that the younger boy, Michael Conner Verkerke, was playing with his younger brother, best friend, and another child at the Kentwood, Mich. playground Monday when the aggressor plunged the knife into his back. According to witnesses, all of the children ran, and Verkerke collapsed on his front porch as his mother screamed for help. He was rushed to the hospital where he later died. 

Glen Stacy told the Associated Press that the unidentified 12-year-old calmly asked to use his phone, calling 911 to turn himself in for the crime. He was briefly hospitalized, then ushered off to Kent County Juvenile Detention Center. Yesterday, he pleaded not guilty to the murder charge, and his attorney is pushing for a psychiatric evaluation to see if he's mentally fit to stand trial. At this time, no motive for the crime has been identified.

Because he's been charged as an adult, he could be sentenced as a juvenile and as an adult once he turns 21 if convicted. 

[via The Associated Press]

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