The FBI hopes new surveillance footage released today will aid in the recovery of 13 priceless artworks stolen 25 years ago and help put to rest one of Boston's greatest mysteries. In the early hours of March 18, 1990, two men dressed as cops were let into the Gardner Museum, where they tied up two security guards and absconded with the artwork and the museum's security footage, the Boston Globe reports. But the thieves, who have never been identified, may have missed one key thing. According to the FBI, surveillance footage from the day before the robbery shows a security guard letting a man into the museum—against protocol—through the same door later used in the robbery.
The Globe reports it's unclear why this footage wasn't viewed by law enforcement earlier, but it could show a "dry run" of the heist. The newspaper identifies Richard Abath as the security guard in the footage, and the FBI is hoping the public can help identify the mystery man he lets in. Abath, a rock musician at the time who now lives in Vermont, has claimed he had no part in the robbery, but this new footage appears to contradict a number of his statements. No one has ever been charged with stealing the art—for which there is a $5 million reward—and no one ever will, as the statute of limitations has expired. Someone in possession of the paintings, however, could face charges. Their total value exceeds $500 million, reports AP. (Read more crime stories.)