On this date 23 years ago, two individuals entered the Gardner Museum in Boston, Massachusetts disguised as police officers. After tying up the museum's real security guards, they spent 83 minutes raiding the facility and emerged with 13 pieces of art including original paintings by Rembrandt, Degas, and Vermeer. In all, the stolen goods were valued at $300 million by the FBI, though other experts say that figure should be closer to $500 million. The Gardner heist remains the single largest property crime in US history, and now more than ever the bureau and museum officials are eager for answers. Today the FBI renewed a campaign to find the missing art relics, offering a $5 million reward for information leading to a successful recovery.

The FBI believes it has identified those behind the heist, but they're essentially cleared of wrongdoing at this point; the statute of limitations on the original theft has already lapsed. Rather than criminal prosecution, the goal now is returning the lifted pieces to the halls of Gardner Museum where they belong. To better the odds of that happening, the FBI wants your help. It's uploaded high-resolution photos of every painting known to be missing in hopes someone on the internet will come to a stunning revelation. "If you didn't see these paintings, you'd walk right by them and maybe not take note of them," says agent Geoff Kelley. "But by trying to get the images out there of these paints and these pieces, hopefully this might resonate with someone." Aside from the website launched today, federal officials will also appeal to the public via billboards in Connecticut and Pennsylvania, two states it believes the pieces were trafficked through.