FLORENCE, Ky. - Northern Kentucky officials said Thursday that they have the DNA of the person who murdered a Boone County couple more than a year ago.
The Boone County Sheriff's Office said in a news conference Thursday morning that they obtained DNA of the person believed to be the killer of Bill and Peggy Stephenson. The couple, both 74, were found dead in their Ridge Edge Court Home in Florence, Ky., over Memorial Day weekend in 2011.
Officials say they are filing the DNA in the FBI's system, but they have not yet found a match. Authorities said they haven't confirmed a specific gender or race of the killer.
The reward for information about the murders has increased to $100,000. Previously, the family offered a reward of $5,000 for information. The increased reward is available for 90 days until Nov. 30, 2012.
So far, the murders have remained unsolved. Investigators have questioned more than 250 people across 14 states in the case, but nobody has been charged. A family member found the couple dead after they went to their home after the couple didn't show up for church, where they were both actively involved.
Authorities said Thursday that they now know the Stephensons' time of death was between 1 a.m. and 4 a.m. and that the suspected killer spent a significant amount of time in the condo after the murders arranging the crime scene in a "unique way," according to lead investigator in the case, Coy Cox.
Cox said with the additional DNA and the increased reward, officials are confident they will find the suspect and bring justice to the Stephenson family.
"We now have his genetic identification and what that means is, in a lot of cases as a detective you might know who did a crime, but never be able to prove it. We have something much better than that now. We can prove who did our crime. It's just a matter of when we put his name on a warrant and arrest him, and that will happen," said Cox.
The Stephenson's three adult children were present at Thursday's press conference. Doug Stephenson, the couple's son, said not a minute goes by his family isn't heartbroken.
"The killer thinks they've gotten away with murder. Nothing could be further from the truth," said Doug Stephenson. "We will never stop looking for you. One day we will stand face to face in a courtroom, and you will face justice for the despicable cowardly act you committed against our family."
To help in the search for information, banners with the increased reward details and tipline will be displayed on parts of I-75 starting Thursday. A new tipline has been set up for people with information. The number is (859) 334-8496. There's also a website dedicated to the case created by the Boone County Sheriff's department.
The Stephensons' nephew, Robert Charles Stephenson, was previously named a person of interest in the case and is charged with murder in an unrelated case involving the death of Leigh Jennings in Indiana. He pleaded not guilty to the Indiana murder charge. On Thursday, authorities said they have tested his DNA, and he was not a match.
Stay with 9 News and WCPO.com for updates as they become available.
-- Sarah Beth Hensley contributed to this report.
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