Michael Lee Shaver told Cass County (Mo.) authorities after his arrest for attempted carjacking that he had killed at least seven people on his land, The Kansas City (Mo.) Star reported Monday. Authorities said "John Doe No. 1" was between the ages of 20 and 26 and was killed in fall 2001.
A search of the property uncovered the remains of two other people, authorities said. The most recent remains were only months old. Cass County Sheriff Dwight Diehl said the search would likely be ongoing for several days.
"A lot of this is going to a lab and it will take some time," Diehl said.
Investigators said they believe the killings took place during drug transactions, and allege that Shaver took drugs and money from the victims.
Shaver had previously been sentenced to four years imprisonment in 1997 after threatening a Kansas City police officer with a knife.