OCONEE COUNTY, Ga. — The Putnam County Sheriff is calling it the best evidence he has had in 10 years in the mysterious killing of a couple in a Lake Oconee neighborhood.

Someone killed Russell and Shirley Dermond in 2014. Deputies have followed hundreds of leads, but they have all led nowhere.

Neighbors found Russell’s decapitated body inside the garage behind one of the couple’s cars, with the 88-year-old’s head nowhere to be found.

Shirley Dermond’s body was found in Lake Oconee after someone apparently tried to weigh it down. The sheriff said she died of blunt force trauma.

“It must have just been a moment of horror, and probably a very long moment of horror, unfortunately. And so, we know that Mom and Dad want us...” the Dermond’s son, Brad Demond said, choking up.

“To keep going and move forward,” his wife Erin said, finishing the thought.

“From the moment that we were notified of this, we were in total horror,” Brad Dermond said.

Putnam County Sheriff Howard Sills has obtained a piece of clothing that belonged to Russell Dermond that had DNA from an unknown individual on it.

Sills said that he has ordered more testing to be done and called the evidence the most promising lead in the case in a decade.

The sheriff remarked that in the 50 years he’s been wearing a badge, there are only two deaths that remain unsolved on his clock.

“Russell and Shirley Dermond,” Sills said.

When asked how often the case is on his mind he said, “Every day. It never goes away,” Sills said.

He still has the evidence that he had in his office from the case, which includes the Dermonds’ computer and the cement blocks used to weigh Shirley Dermond down in the water.

“We’re still just totally in the dark as to why this took place,” Brad Dermond said.

Brad Demond said the new evidence is giving him a sliver of hope that his parents’ killer will be found.

One of those labs that did the DNA testing is Ortham Labs in Woodlands, Texas. The sheriff said after finding some DNA, Ortham Labs referred him to Sorensen Forensics in Utah. Sills said he personally delivered the evidence to them. That lab also found DNA.

Sills said they are still looking for more DNA to get to the next step of either running the results through a national database of through genealogical data to identify a suspect.

Sills is quick to point out that no suspect has been identified in the case, but the new evidence could go a long way to finding out who killed the couple.