BOULDER, Colo. (Reuters) - New DNA tests have definitively cleared the parents of child beauty queen JonBenet Ramsey of her unsolved murder almost 12 years ago, prosecutors said on Wednesday.

Patsy Ramsey looks down as her husband John (R) produces a picture of JonBenet Ramsey during a press conference in Atlanta, May 5, 2000. REUTERS/Tami Chappell

In a statement seeking to silence suspicions surrounding relatives of the slain 6-year-old, prosecutors said new testing techniques on male DNA found on JonBenet’s clothes did not match any family members.

“This new scientific evidence convinces us that it is appropriate ... to state that we do not consider your immediate family, including you, your wife Patsy, and your son Burke, to be under any suspicion in the commission of this crime,” Boulder County District Attorney Mary Lacy said in a letter to JonBenet’s father, John Ramsey.

JonBenet Ramsey was found beaten and strangled in the basement of her parents’ home in Boulder, Colorado, on December 26, 1996.

Videos of the tiny blonde competing in child beauty pageants, and the suspicion surrounding her parents, made headlines around the world. No one has ever been charged.

JonBenet’s mother, Patsy, died of ovarian cancer in 2006, still fighting to clear her name.

“The suspicions about the Ramseys in this case created an ongoing living hell for the Ramsey family and their friends, which added to their suffering from the unexplained and devastating loss of JonBenet,” Lacy said in a separate statement on Wednesday.

Lacy apologized for the distress caused to the Ramseys and said she wished her office could have cleared them before Patsy Ramsey died.

The new tests were done on DNA samples taken from long johns and underwear worn by JonBenet at the time of her death. Prosecutors now believe the DNA profile belongs to the unknown perpetrator of the crime, she said.

The DNA profile has been entered into a national crime database but no matches have turned up, Lacy said.

The murder made headlines again two years ago when an American teacher living in Thailand, John Mark Karr, claimed he was involved in JonBenet’s death. DNA tests proved he was not at the scene of the crime.