BOULDER, Colo. (NBC) -- Prosecutors say new DNA tests have cleared JonBenet Ramsey's family in the 1996 killing of the 6-year-old beauty queen.

Boulder County District Attorney Mary Lacy said Wednesday the tests point to an "unexplained third party."

She says prosecutors don't consider any member of the Ramsey family to be a suspect.

JonBenet's parents, John and Patsy Ramsey, were long said to be under an "umbrella of suspicion" in the girl's slaying.

Lacy apologized to the family on Wednesday, saying, "To the extent that this office has added to the distress suffered by the Ramsey family at any time or to any degree, I offer my deepest apology."

John Ramsey, a software entrepreneur, has said in interviews he believes the case will be solved.

Patsy Ramsey died June 24, 2006 of ovarian cancer at the age of 49 in Atlanta, where the family moved after JonBenet's death.