The Osage County Sheriff’s Office searched Dennis Rader’s former home in Park City, Kansas on Tuesday.

According to the sheriff’s office, they were looking for evidence that may be tied to the disappearance of Cynthia Dawn Kinney from Pawhuska in 1976.

“This ongoing investigation has uncovered potential connections to other missing persons cases and unsolved murders in the Kansas and Missouri areas, which are possibly linked to Dennis Rader. The Osage County Sheriff’s Office has been working alongside the Kansas Bureau of Investigation (KBI), sharing crucial information and collaborating on this case.” The sheriff’s office said.

Deputies said items of interest were recovered at the scene and will undergo a thorough examination to see if they’re related to Kinney’s disappearance.

“At this stage, Dennis Rader is considered a prime suspect in these unsolved cases, including the Cynthia Dawn Kinney case from Pawhuska.” OCSO said.

In 2005, Dennis Rader confessed to killing 10 people over the course of three decades in the Wichita area.

He called himself BTK, or the BTK killer, which stands for: bind, torture, kill.