A Burlington County man has pleaded guilty to fatally beating his 77-year-old mother, putting her body into a chest, loading it into his car, and abandoning the vehicle in the parking lot in front of the Willingboro pizza store where he worked, prosecutors announced Friday.

Brian K. Templeton, 54, pleaded guilty to aggravated manslaughter and will be sentenced to 25 years in prison. He will not be eligible for parole for at least 21 years, Burlington County Prosecutor Scott Coffina said.

Templeton, who lived with his mother in the Edgewater Park Apartments, was arrested in November, a few days after an employee of the apartment complex called police for a wellness check on Templeton’s mother, Doris, who had not been seen in two weeks.

Investigators quickly discovered that on Oct. 24, Templeton had killed his mother and driven to his workplace. They said he then began using his mother’s car. Detectives found Doris Templeton’s remains inside the abandoned vehicle. She died of blunt force trauma to the head, prosecutors said.

Templeton is scheduled to be formally sentenced at a hearing on Oct. 23.