Bennett and his wife Carol, both 63, were found by a friend who performed a welfare check after phoning Todd County Sheriff's Office to report that they had not responded to texts or phone calls since Tuesday.
Authorities said both died under “suspicious circumstances” at their home in Long Prairie, a town of about 3,500 about 30 miles east of Alexandria.
The sheriff's office in a statement Friday that they are "awaiting word" on the cause and manner of the deaths.
A 22-year-old man is being sought in connection with the case. He was identified as Dylan John Bennett, the couple son, who was sitting with them at the time.