MINNEAPOLIS (WCCO) — Seventeen-year-old Trashaun Morris was tried and charged as an adult Monday for the March 24 murder of 19-year-old Billy Ray Robles.

A judge added two second-degree murder charges and one third-degree murder charge to Morris’ initial charges of first-degree riot and second-degree assault, stemming from a shooting in Inver Grove Heights earlier this year.

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Morris and Robles had been aboard a party bus with 40 other people celebrating a friend’s birthday when a fight broke out. As Robles stepped in to try to deescalate the situation, Morris allegedly began shooting, killing Robles and wounding another.

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Billy Ray Robles (credit: Facebook)

Monday was Morris’ first court appearance on the new charges, and his next appearance is set for Oct. 18.

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Dakota County Attorney James Backstrom announced Morris is certified to stand trial as an adult.