PAYNESVILLE, Minn. (WCCO) — A Paynesville man who was charged with killing his grandparents in March pleaded guilty to the charges Thursday.

Gregory Allen Scheel, 34, was accused of killing Wilbert and Gloria Scheel, who were found dead in their Toyota Prius on a rural road March 22. The couple had been reported missing the day before when they didn’t show up for a family dinner.

According to the criminal complaint, Scheel choked his grandfather with a plastic bag after tying his arms and legs. He is accused of strangling Gloria Scheel with an electrical cord.

Scheel’s two first-degree murder charges both carry a mandatory life sentence.

Sentencing is scheduled for Oct. 4.