A Paynesville, Minn., man whose grandparents took him in when he was struggling admitted on Thursday that he killed them.

Gregory Scheel, 34, pleaded guilty to two counts of first-degree murder in the March deaths of Wilbert "Willie" Scheel, 93, and Gloria Scheel, 80. Gregory Scheel made his plea in Stearns County District Court and was taken immediately to prison.

First-degree murder carries a mandatory life sentence, said the Stearns County Attorney's Office, which announced the plea. Scheel will receive consecutive life sentences when he is sentenced on Oct. 4, said Ole Tvedten, chief of the County Attorney's criminal division. He could be eligible for parole in 60 years.

The grandparents' bodies were found on March 22 in their car on a rural dirt road in neighboring Kandiyohi County, covered with a carpet. The interior of their vehicle was partly charred and covered in soot.

A medical examiner ruled their deaths homicides. Willie Scheel was suffocated with a plastic bag placed over his head, and Gloria Scheel had been strangled with an electrical cord.

Suspicion quickly turned to their grandson, who had been living with them for several months, and who throughout his adult life had racked up at least 15 convictions for burglary, theft, receiving stolen property, domestic assault, drug possession, violating a protection order and drunken driving.

Gregory Scheel was arrested that night after a manhunt by more than a half-dozen local and state law enforcement agencies.

The deaths shocked Paynesville, a city of 2,400 residents about 85 miles west of the Twin Cities, where the couple were remembered as important members of their community and their church.

"It's a small community and these people were known by everyone — I mean, all of the Paynesville royalty — for just many, many years," said Linda Liestman.

Gloria Scheel was president of a women's group at Grace United Methodist Church for years and oversaw the annual Christmas pageant. Willie Scheel was a well-known businessman who took Colorado skiing trips into his 80s, played competitive pingpong and drove the local beauty queens in summer parades in his classic convertibles.

"They were two people who would help you no matter what you did," said Kari Schaefer, director of youth and family ministries at Grace United.

At the time of his arrest, Gregory Scheel was facing charges in Chippewa County for burglary, theft and escape involving an incident in which he allegedly stole a box of toys off the doorstep of the home to which they'd been delivered.