Update, 5:30 p.m. ET: A law enforcement official tells CBS News correspondent Bob Orr that "promising lead" reported here and elsewhere has apparently washed out. The FBI had been tipped that a man who died about 10 years ago might have been Cooper. An item once belonging to that man was analyzed for fingerprints in an effort to match prints found aboard the plane D.B. Cooper hijacked. No usable prints were found on the item.
The FBI has not officially cleared this latest potential suspect, but sources tell CBS News they are in the process of ruling him out.
In over 40 years since the Cooper hijacking, officials have investigated more than 1,000 potential suspects, and while FBI officials continue pursuing a number of information streams, the skyjacking mystery endures.
SEATTLE -- The FBI says it has a "credible" lead in the D.B. Cooper case involving the 1971 hijacking of a passenger jet over Washington state and the suspect's legendary parachute escape.
The fate and identity of the hijacker dubbed "D.B. Cooper" has remained a mystery in the 40 years since a man jumped from a Northwest Orient Airlines 727 flight with $200,000 in ransom.
The recent tip provided to the FBI came from a law enforcement member who directed investigators to a person who might have helpful information on the suspect, FBI spokeswoman Ayn Sandalo Dietrich told The Seattle Times on Sunday. She called the new information the "most promising lead we have right now," but cautioned that investigators were not on the verge of breaking the case.
"With any lead, our first step is to assess how credible it is," Sandalo Dietrich told the Seattle Post Intelligencer on Saturday. "Having this come through another law enforcement (agency), having looked it over when we got it it seems pretty interesting."
Dietrich says an item belonging to the suspect was sent to a lab in Virginia for forensic testing.
But Geoffrey Grey, author of "Skyjack: The Hunt for D.B. Cooper," tells CBS News finding fingerprints on the item may be difficult.
"When this case happened in the 1970s," Grey points out, "the era of DNA was not upon us, and agents really didn't look out to preserve this evidence in the way we do now."
Dietrich did not provide specifics about the item or the man's identity.
Federal investigators have checked more than 1,000 leads since the suspect bailed out on Nov. 24, 1971, over the Pacific Northwest, and there have been several deathbed confessions, Orr says.
The man who jumped gave his name as Dan Cooper, but Orr notes that no one knows if he survived, or even if he gave his real name. Some believe he was inspired by Canadian comic Dan Cooper, a test pilot who parachuted from planes.
The man claimed shortly after takeoff in Portland, Oregon, that he had a bomb, leading the flight crew to land the plane in Seattle, where passengers were exchanged for parachutes and ransom money.
The flight then took off for Mexico with the suspect and flight crew on board, before the man parachuted from the plane.
This may, Orr observes, be the best clue since 1980, when an eight-year-old boy in Washington State discovered nearly $6,000 cash during a family picnic. The serial numbers matched those of the ransom money.
Word of the FBI's newest tip was first reported by The Telegraph newspaper in London.