SEATTLE (Reuters) - Four decades after a skyjacker dubbed D.B. Cooper bailed out of a U.S. jetliner in mid-air and vanished with $200,000 in cash, federal agents are pursuing new clues pointing to a suspect they believe is long dead, an FBI spokesman said on Tuesday.

The latest lead in the case originated with a source in law enforcement, who directed agents to a person who was close to the suspect and obtained objects now being analyzed to see if they bear fingerprints matching those left by the hijacker on the plane, said Frederick Gutt, FBI special agent in Seattle.

Gutt declined to reveal the law enforcement source, the person the FBI was led to, or the deceased individual whose fingerprints were being examined.

But he said the suspect in question is someone who was not previously known to investigators.

The case of D.B. Cooper, a moniker given to the skyjacker by the media after he disappeared, has endured as one of America's great unsolved mysteries.

It began when a dark-haired man who appeared to be in his mid-40s, dressed in a business suit and tie, hijacked a Seattle-bound Northwest Orient Airlines flight from Portland, Oregon, on November 24, Thanksgiving eve, 1971.

The man, calling himself "Dan Cooper," slipped a note to a flight attendant after takeoff saying he had a bomb, then opened his briefcase to reveal red-colored sticks attached to a mass of wires, according to an FBI online account of the case.

The plane landed in Seattle, where he freed the 36 other passengers in exchange for $200,000 in cash from the airline and four parachutes but kept several crew members aboard as the plane took off again, ordered this time to fly to Mexico.

He ended up jumping out of the back of the jetliner into the night with a parachute and the ransom money somewhere between Seattle and Reno, Nevada, over what was believed to be a rugged, wooded area.

According to the Seattle Times, the plane was flying through a storm at about 10,000 feet at the time, with the air temperatures outside at about seven degrees below zero. The plane landed safely, but Cooper was never seen again.

He was believed by some to have likely perished when he bailed out of the aircraft. The only trace from his getaway was a crumbling package of $20 bills matching the ransom money's serial numbers, unearthed by a young boy from a sandbar along the Columbia River in 1980.

The FBI official said that authorities have ruled out Kenny Christiansen, a former Northwest employee once suspected in the case. The FBI said it had considered over 800 suspects in all by the fifth anniversary of the hijacking.

"Yes, there is a lead in this matter that's being pursued," Gutt told Reuters. "It's someone who surfaced who hasn't surfaced before. It came from someone who's close to someone who is deceased. So far, we haven't been able to dismiss it."

He added: "We're seeking to compare prints and finding stuff that can add more solid evidence. We have to wait. We're still recovering some additional items. It's a process, and it's not a priority matter."

He also said the new lead, first reported over the weekend by The Telegraph newspaper in London, actually originated over a year ago.

(Writing and additional reporting by Steve Gorman; Editing by Dan Whitcomb, Greg McCune and Cynthia Johnston)

Source: Reuters US Online Report Domestic News

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