Stevens County Deputy Prosecutor Lech Radzimski said the unidentified boy, on advice of defense attorney Helen Hokom, entered the surprise guilty plea Monday at a hearing in which the defense planned to argue for suppressing evidence in the case.
The boy, and an 11-year-old accomplice, were taken into custody after a third boy, Justin Sanders, told authorities he had seen the pair play with a knife the 10-year-old had in his backpack, KXLY-TV, Spokane, reported.
The two alleged conspirators intended to attack a classmate that day, Colville police officer Scott Arms said.
They were promptly expelled from school and taken into custody, accused of conspiracy to commit murder, witness tampering and juvenile possession of a firearm, KXLY-TV said, noting the 11-year-old was not a party to the guilty plea of the 10-year-old.
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