CHARDON, Ohio (AP) — A 17-year-old charged in the school shooting deaths of three students in Ohio this winter is set to be arraigned Friday afternoon.

A grand jury earlier this week indicted the boy on three counts of aggravated murder along with two counts of attempted aggravated murder and one count of felonious assault.

A judge ruled last month that T.J. Lane will be tried as an adult in the February shootings at Chardon High School, east of Cleveland.

He could face life in prison if convicted.

No motive has been established.

Prosecutors say Lane has admitted taking a .22-caliber pistol and a knife to the school and firing 10 shots at a group of students in the cafeteria at the start of the school day.

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