A suspect in the fatal shooting of a Mat-Su teen last year has pleaded guilty to manslaughter in the case.

Damien Peterson, 20, entered his plea Thursday in the June 27, 2016 shooting of 16-year-old Frank Woodford. Charges against Peterson of second-degree murder and criminally negligent homicide were dropped by prosecutors under the terms of his plea agreement.

Peterson will be sentenced on May 9, when he faces a maximum prison term of 20 years. The prosecutor in the case said Thursday that the presumptive sentencing range for manslaughter is five to nine years, under recent sentencing guidelines set by Senate Bill 91.

Alaska State Troopers had initially found no conclusive signs of foul play in Woodford’s shooting, which occurred while Woodford was in a bedroom at a Wasilla home with Peterson and Austin Barrett, a suspect in the murder of 16-year-old David Grunwald.

Before he died, Woodford told medics and troopers that he had not shot himself in the chest. Peterson denied that account, however, and troopers said there wasn’t any conclusive evidence of foul play in Woodford’s shooting until after Grunwald’s murder.

In a criminal complaint against Woodford, a witness told troopers that Peterson had pointed a gun at the witness’s head and chest before pointing it at Woodford and pulling the trigger. Afterward, Peterson told the witness Woodford had shot himself.

Peterson’s brother, Devin Peterson, had been charged with evidence tampering and hindering prosecution in Grunwald’s death.

Heather Hintze contributed information to this story.

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