KNOXVILLE, Tenn. (AP) -- Prosecutors want to try a 15-year-old charged with fatally shooting a classmate in his school cafeteria in Knoxville as an adult.

John Gill, special assistant to the district attorney, said Thursday a petition will be filed to move Jamar Siler from juvenile court to adult criminal court, where the potential penalty would rise exponentially.

Siler is charged with first-degree murder in the death of 15-year-old Ryan McDonald last week at Central High School. If convicted in juvenile court he could not be incarcerated past the age of 19. In adult court, the sentence could be at least 51 years in prison.

A juvenile court judge will decide at a hearing on Oct. 9.

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