In this handout image provided by the Sedgwick County Sheriff's office, BTK murder suspect Dennis Rader stands for a mug shot released February 27, 2005 in Sedgwick County, Kansas. (Photo by Sedgwick County Sheriff's Office via Getty Images)
Oklahoma investigators were in Kansas on Tuesday, as officials say they are investigating missing persons and murder cases which might be tied to serial killer Dennis Rader, who's also known as BTK for his preference to "bind, torture and kill," his victims.
Rader confessed to killing 10 people after being arrested in 2005. Investigators were back at Rader's former Park City, Kansas, property Tuesday to follow-up on leads of murders and missing people which may be tied to Rader.
"Osage County Sheriffs Office is continuing to follow leads in unsolved missing persons and murder cases possibly related to BTK. The investigation is ongoing at this time, and I still have investigators out in the field so I can’t comment any further," Undersheriff Gary Upton said.
WICHITA, KS - AUGUST 18: BTK killings victim families gather for a press conference after a trial reached a verdict at the Sedgwick County Courthouse on August 18, 2005 in Wichita, Kansas. Dennis Rader of Park City, Kansas pleaded guilty to the 10 k …
Park City police and the Kansas Bureau of Investigation was also present as investigators searched Rader's former property, which is now city-owned property.
SERIAL KILLER BTK SAYS PRISON CELL SEARCHED AMID COLD-CASE PROBES; DENIES INVOLVEMENT
Upton said the search spiraled from the investigation into Cynthia "Cyndi" Dawn Kinney, a 16-year-old cheerleader who was last seen leaving a relative's laundromat on June 23, 1976.
Fox News Digital previously reported that prison guards seized Rader's belongings during a meeting with cold-case investigators.
Dennis Rader, the admitted BTK serial killer, sits in court on the first day of his sentencing at the Sedgwick County Courthouse August 17, 2005 in Wichita, Kansas. Rader, of Park City, Kansas, has pleaded guilty to 10 killings dating back to 1974. …
Kerri Rawson, Rader's daughter, told Fox News Digital on Tuesday that "The theory is he could have placed evidence of cases under stone pavers under the metal shed he built early to mid 90s. Like drivers licenses in jars."
SERIAL KILLER BTK LAYS OUT ALIBI AMID NEW QUESTIONING OVER 1976 OKLAHOMA COLD CASE
She said investigators dug a hole where the shed used to be.
Rader has previously denied involvement in the cold case and said he was "done" speaking with Osage County Sheriff Eddie Virden, but said he "enjoyed" meeting with investigators regarding the disappearance of Shawna Garber, who went missing on Halloween in 1990.
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