A teenage boy will be prosecuted as an adult in the one-punch attack in a St. Cloud alley that left a 20-year-old Twin Cities man dead.

Jesse J. Smithers, 17, of Sauk Rapids, Minn., appeared on Monday in Stearns County District Court on charges of second-degree murder, first-degree manslaughter and first-degree assault in the Sept. 20 death of Colton R. Gleason, of Greenfield.

Smithers remains held in lieu of $500,000 bail.

Police and family members say it does not appear that Gleason knew Smithers. Authorities have not revealed what prompted the attack.

According to police and prosecutors:

Smithers was in a vehicle driving just west of St. Cloud State University through an alley where Gleason and two women were walking at about 11:20 p.m. Smithers got out, approached the three and punched Gleason in the head, causing him to hit his head on the ground. He died the next day at St. Cloud Hospital.

Gleason's family said he was attending Minnesota State University, Mankato, visiting friends in St. Cloud and had planned to leave soon for a bike trip to northern Minnesota with his parents.