ST. CLOUD (AP) -- A man has been convicted of killing his grandparents at a home he shared with them in Paynesville.

Thirty-four-year-old Gregory Allen Scheel pleaded guilty in Stearns County District Court to two counts of first-degree murder Thursday.

Scheel cried when he admitted to assaulting and murdering 93-year-old Willie Scheel and 80-year-old Gloria Scheel on March 21st at their home.

Scheel put a plastic bag over his grandfather's head and a ligature was used to tie the bag around his neck. He died from asphyxiation. The grandson then wrapped an extension cord around his grandmother's neck and strangled her. He drove the bodies to Kandiyohi County where he lit the car on fire.

The guilty plea carries a mandatory life sentence.  The Stearns County Attorney's Office says the two counts will be sentenced consecutively and Scheel will not be eligible for parole for at least 60 years.

Scheel was committed to prison following Thursday's plea and he will be formally sentenced on October 4th.