D.B. Cooper
A 1971 artist's sketch of the alleged hijacker D.B. Cooper. FBI

The FBI claims to have a "credible" lead in the mysterious case of a 1971 hijacking of a passenger airliner by a man known as "D.B. Cooper."

The hijacker parachuted out the back of a plane with $200,000 and was never seen again.

The suspect is now dead, but a piece of the man's property handed over by an unidentified informant is currently being processed at the FBI forensic lab in Quantico, Va., for fingerprints to confirm if he, indeed, was the alleged hijacker.

FBI spokeswoman Sandalo Dietrich said, "We hope to compare it to partial fingerprints we got in the hijacking."

Some of the only physical evidence that investigators had of "Cooper" was a partial DNA sample from a clip-on tie that was left behind on the plane.