BOULDER, Colo. -- After 12 years of suspicion that drove JonBenet Ramsey's parents halfway across the country, new DNA tests convinced prosecutors of what the couple said all along: They didn't kill their little girl. A mysterious stranger did.

Video: Family Members Cleared
Video: John Ramsey Interview

Colorado TV station KUSA reported the announcement Wednesday afternoon. The Denver station also reported that the newly discovered evidence does not match anyone in the law enforcement database to the slaying.

Prosecutors' surprising announcement Wednesday affirmed the hopes of the 6-year-old girl's father, John Ramsey, that her killer might one day be found. Her mother, Patsy, did not live long enough to finally see her name cleared.

New technology was used to analyze the scant DNA left behind when someone grasped JonBenet's long johns. That combined with matching DNA found earlier in a drop of blood on JonBenet's underwear convinced prosecutors that the genetic material is that of the still-unidentified killer.

"The most important thing is that we now have very, very solid evidence, and that's always been the hope, at least in the recent past, that that will lead us to the killer eventually," John Ramsey told KUSA-TV.

John Ramsey found his daughter's strangled and bludgeoned body in the basement of the family's home in Boulder on Dec. 26, 1996. Patsy Ramsey said she found a ransom note demanding $118,000 for her daughter.

For years after the slaying, tabloids and crime shows went after the couple. In 1997, Boulder County's district attorney at the time, Alex Hunter, said the parents were under an "umbrella of suspicion." Early in the case some news reports even cast suspicion on JonBenet's older brother, Burke, who was 9 when his sister was killed.

"To the extent that we may have contributed in any way to the public perception that you might have been involved in this crime, I am deeply sorry," District Attorney Mary Lacy wrote in a letter to John Ramsey. "No innocent person should have to endure such an extensive trial in the court of public opinion."

Lacy was elected district attorney in 2000, when her predecessor stepped down. Ramsey said he understood that Lacy was apologizing for some early mistakes in the case but said he believes she had "always done the right thing and the courageous thing."

Lacy said new "touch DNA" tests on skin cells that were left behind on JonBenet's long underwear point to an "unexplained third party" and not a member of the family.

The suspicions against the Ramseys outlived Patsy, who was 49 when she died of cancer in 2006 in Atlanta, where the family moved after JonBenet's death.

"My first thought was obviously I wish Patsy Ramsey was here with us to be able to at least share vindication of her family," said L. Lin Wood, an attorney for the Ramsey family. "There are many people in this country, if not around the world, that also owe John and Patsy Ramsey and Burke Ramsey an apology."

John Ramsey, a software entrepreneur who now lives in Michigan, said he is hopeful the killer will be found.

"I think the people that are in charge of the investigation are focused on that, and that gives me a lot of comfort," he told KUSA. He added: "Certainly we are grateful that they acknowledged that we, based on that, certainly could not have been involved."

Early in the investigation, police found male DNA in the drop of blood on JonBenet's underwear and determined it was not from anyone in her family. But Lacy said investigators were unable to say who it came from and whether that person was the killer.

Then, late last year, prosecutors turned over long underwear JonBenet was wearing to the Bode Technology Group near Washington, which looked for "touch DNA," or cells left behind where someone has touched something.

The lab has been using this technology for only about three years.

The laboratory found previously undiscovered genetic material on the sides of the girl's long underwear, where an attacker would have grasped the clothing to pull it down, authorities said.

Lacy said in a statement that the presence of the same male DNA in three places on the girl's clothing convinced investigators it belonged to JonBenet's killer and had not been left accidentally by an innocent party.

"It is therefore the position of the Boulder District Attorney's Office that this profile belongs to the perpetrator of the homicide," she said. In her letter to the Ramseys, she said the DNA evidence "has vindicated your family."

She said investigators hope someday to find a DNA match in the ever-expanding national DNA databank.

Through a spokeswoman, Lacy declined to comment any further.

Lacy had previously expressed doubts that the parents were involved. In 2003, a federal judge handling a defamation lawsuit in Atlanta involving the Ramseys said evidence in the case was more consistent with the theory that an intruder killed JonBenet, and Lacy said she agreed.

Less than two months after Patsy Ramsey died, the case appeared to blow wide open with the arrest in Thailand of John Mark Karr, a sometime teacher obsessed with the little girl's slaying. Karr made bizarre, detailed confessions to the killing, but authorities said DNA evidence showed he did not commit the crime.

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