When the decapitated body of Joie Ruth Armstrong was found, eyewitnesses said they saw a blue 1979 International Scout parked outside the cabin where she was staying. Detectives traced this vehicle to Stayner, which led to him becoming the prime suspect in the case. FBI agents John Boles and Jeff Rinek found Stayner staying at the Laguna del Sol nudist resort in Wilton, where he was arrested and taken to Sacramento for questioning. During his interrogation, Stayner shocked the agents when he confessed not only to Armstrong's decapitation, but to the murders of Pelosso and the Sunds, and the sending of the map for finding Juli Sund's body as well. His vehicle yielded evidence proving his link to Armstrong.