Twenty-six years after the brutal slaying of pageant princess JonBenét Ramsey, authorities are still searching for the individual responsible for her death.

On Dec. 26, 1996, a 911 call was placed reporting a missing 6-year-old girl in Boulder, Colo. JonBenét's parents, John and Patsy Ramsey, found a handwritten ransom note demanding $118,000 for the return of their daughter.

Later that day, JonBenét's badly beaten body was found in the basement of the Ramsey home. She had also been sexually assaulted and strangled to death.

The case has puzzled authorities over the years as countless theories and tips regarding what happened have been presented and unverified.

In the new documentary Suburban Nightmare: JonBenét Ramsey, John urges authorities to release never-before-seen DNA evidence for further testing, in hopes of finding her killer.

"This was an evil, sick person," John told People, adding that the FBI believed the individual who killed JonBenét was either "very angry" or "very jealous" of him.

"This had nothing to do with JonBenét. It was a heavy burden to hear," he continued. "There were times for a long time after JonBenét was killed that I wanted to die. The pain was so intense."

Despite over two decades passing, the 79-year-old grieving father remains hopeful that DNA will eventually solve the case.

Last month, authorities revealed they would be working with the Colorado Case Review Team to take a fresh look at the murder of the little girl. John is hopeful that the unidentified male DNA collected from JonBenét's clothing will be tested, and yield a match, finally putting the case to rest.

"I'm pretty confident that's going to yield some results," he told the outlet. "But we don't know until we try. We know there's more that can be done."

Early on in the investigation, John and Patsy Ramsey were considered suspects by Boulder police, however, John maintains they are innocent. Patsy passed away on June 30, 2006, after a long battle with ovarian cancer.

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