Could we finally have an answer in who killed JonBenet Ramsey? Police say they continue to check DNA.

Could DNA technology improvements help solve one of the country’s most famous cold cases?

Boulder police say they continue to work with labs to check DNA from the scene of JonBenet Ramsey’s murder. Boulder police made the announcement days ahead of the 25th anniversary of Ramsey’s killing.

On Dec. 26, Ramsey — who was 6-years-old and a pageant queen — was reported missing by her family after finding a ransom note. Hours later, Ramsey was found dead in the basement of her home. She was found with a rope around her neck and a fractured skull.

In the 25 years since, police have not made an arrest in the case.

Some believed Ramsey’s parents, John and Patsy, played a role in the murder or covering up the crime. Others believed an intruder came into family Boulder’s home to kill the child. Many people blame police for botching the investigation.

As of this month, police said the evidence has included nearly 1,000 DNA samples.

“Thanks to the huge advances in DNA technology, multiple suspects have been run through the system to check for matches. CBI has updated over 750 reference samples with the latest DNA technology,” a statement from police read.

Boulder police works with state agents to make sure DNA samples can be compared correctly to new DNA samples.

“That DNA is checked regularly for any new matches,” police noted.

In total, Boulder police have reviewed more than 21,000 tips and traveled to 19 states to speak with 1,000 people as part of the investigation.