A sheriff’s office in Oklahoma said self-proclaimed BTK serial killer Dennis Rader is a “prime suspect” in Cynthia Dawn Kinney’s 1976 disappearance, but the local district attorney now says there’s not enough information despite recently requesting a formal investigation on the case. District Attorney Mike Fisher said during a press conference on Monday he’s not at a point where he could file charges against Rader, who is currently behind bars for the murders of 10 people between the 1970s and the 1990s. But Mr Fisher had asked the Oklahoma State Bureau of Investigation to open a formal investigation into Ms Kinney’s disappearance because of the public interest in the revived cold case, and he will file charges if he learns of evidence that would warrant it, he said. Osage County Sheriff Eddie Virden fired back at the DA in his own press conference the following day, saying that he was “absolutely furious” at the comments regarding the case. “District Attorney Fisher attempted to derail the investigation by contacting the prison where Dennis Rader is held in an attempt to halt further interviews between Dennis Rader and our Investigators,” the agency said in a release. He said the DA’s comments were based on incomplete information and did not accurately represent the OCSO’s efforts or the progress that has been made. The sheriff also revealed that while he was in an interview with Rader on Monday afternoon, the convicted killer told him, “guess I’m cleared,” according to what he heard from the DA on the news that officials “don’t have anything.” Sheriff Virden said the matter will be addressed in the proper channels. He added that they have numerous leads they will keep pursuing. “We’ll continue to push for justice, honest and true,” he said. “We have something behind us and that’s the honest truth.” Rader, now 78, gave himself the nickname BTK — for “bind, torture and kill,” played a cat-and-mouse game with investigators and reporters for decades before he was caught in 2005. He ultimately confessed to 10 killings in the Wichita, Kansas, area, about 90 miles (144.84 kilometers) north of Pawhuska. He is imprisoned for 10 consecutive life terms. Last month, Rader was named the prime suspect in the 1976 disappearance of 16-year-old Cynthia Dawn Kinney in Pawhuska, Oklahoma, and in the 1990 murder of 22-year-old Shawna Beth Garber in McDonald County, Missouri. Ms Kinney was last seen at a laundromat. A bank was installing new alarms across the street from that laundromat, Osage County Sheriff Eddie Virden has said. Rader was a regional installer for security system company ADT at the time, but Virden wasn’t able to confirm that Rader installed the bank’s systems. Sheriff Virden told KAKE-TV he decided to investigate when he learned that Rader had included the phrase “bad laundry day” in his writings. DA Fisher said he sat in on interviews that Kansas, Missouri and Oklahoma investigators conducted with Rader about 90 days ago, but the sheriff has not shared any physical evidence with the DA’s office. On Monday, the DA called the information he has received so far “rumours because they’ve not been substantiated yet.” And he said he hadn’t seen anything “that at this point arises to the level of even reasonable suspicion.” He said he had seen things that gave him “pause and concern” about the sheriff’s department, including the way they handled a dig for evidence at Rader’s former property in Park City, Kansas, last month. And he called his relationship with the sheriff “broken.” “I’m not trying to create a conflict with the sheriff of Osage County,” he said. “But, there are certain ways to investigate a case, and I’m concerned that those proper investigative techniques have not been used. That’s why I asked the OSBI to assist.” The prosecutor said he was also concerned for Kinney’s parents, with whom he met for about two hours on Friday. He said they are both in their 80s, and the renewed speculation has taken a physical toll on them. “Cynthia went missing 47 years ago. They’ve got no answers,” Mr Fisher said. “We have reason to believe that it may have been a homicide. We can’t say that with any absolute certainty, but we’ve seen nothing to suggest otherwise as there’s been no contact with Cynthia Dawn since 1976, since her disappearance.” Hours after the DA said there was insufficient information to pursue charges against serial killer, the sheriff announced a National BTK Task Force to provide assistance in the cold case of Ms Kinney. The team includes several renowned experts in the field, including several agencies, Nancy Grace, Former Prosecutor & Media Personality, Sheryl “Mac” McCollum, Task Force Coordinator and CSI, Paul Holes, Cold Case Investigator and Rader’s own daughter Kerri Rawson who has been assisting investigators with the case. Last month, the Osage County Sheriff’s Office released never-before-seen drawings from the killer they believe may hold the key to solving a missing persons case and several homicides. The chilling images depict three different women who are bound and gagged in what appear to be barns, which investigators believe could be in Oklahoma, Kansas and Missouri. Hundreds of Rader’s drawings and writings were recovered after his arrest in 2005, but Sheriff Virden says the images may confirm more crimes were committed. Law enforcement also recently dug up Rader’s former family residence, and reportedly found a “pantyhose ligature”. Rader is currently incarcerated at the El Dorado Correctional Facility in Kansas. Read More Woman bound and gagged in BTK serial killer’s drawing has potentially been identified BTK serial killer’s chilling drawings released amid search for new victims The BTK killer’s need for notoriety led to his capture a decade ago. He’s now a ‘prime suspect’ in at least two other murders