Law enforcement on Friday identified the victims as 22-year-old Danielle Jacobson, 16-year-old John Lajeunesse and two 17 year olds, Steven Presley and Dominic Davis.
Investigators said a person of interest in the case was located in Rhea County overnight and taken into custody on an unrelated charge.
The car containing the bodies was discovered by a resident of the community about 50 miles west of Knoxville on Thursday morning.
The former resort had had controlled access with a gate until 2010, when new owners got rid of it. That move gave rise among some residents about security in the 3,000-acre community.