Headstone of JonBenet Ramsey near Atlanta, where the family had lived before moving to Boulder, Colorado.
CNN  — 

It’s been 25 years since the murder of 6-year-old JonBenet Ramsey riveted the nation, and now Boulder, Colorado, investigators say they have analyzed almost 1,000 DNA samples to find the killer.

It is the latest in a string of numbers that reveal their ongoing efforts:

  • Police have received, reviewed or investigated more than 21,000 tips, letters and emails.
  • Detectives have traveled to 19 states.
  • They have interviewed more than 1,000 people.
  • They have processed more than 1,500 pieces of evidence.

Still, the case remains unsolved. It seized the public interest, due perhaps to a mix of factors, including her involvement in beauty pageants for young girls, her family’s wealth, and suspicion around her parents, who were never charged and later cleared by authorities through DNA testing.

On December 26, 1996, JonBenet was reported missing from the family’s Boulder home. Her mother, Patsy, told police she found a ransom note demanding $118,000 for the girl’s return.

Her body was found that day in a basement room of the home.

Police later revealed her skull had been fractured.

Patsy Ramsey died of ovarian cancer in 2006.

In a statement marking the 25th anniversary of the murder, Boulder police said they actively “use new technology to enhance the investigation” and check regularly for DNA matches in order to solve this case.

“Thanks to the huge advances in DNA technology, multiple suspects have been run through the system to check for matches. CBI (Colorado Bureau of Investigation) has updated over 750 reference samples with the latest DNA technology. The Boulder Police Department works closely with CBI on future DNA advancements.”