LIVERMORE (CBS 5) – It was one of the greatest mysteries of the 1970s. Hijacker D.B. Cooper jumped out of a plane and was never seen again. Nearly four decades later, the cold case is warming up, as an Oklahoma woman has come forward claiming to be Cooper’s niece.

A Bay Area man also has a connection to the case. Jack Almstad of Livermore was on that November 24, 1971 flight. He found himself alone with Cooper in the back of the plane while they circled Seattle.

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“I said, ‘Gee, we were up here so long, if we wait any longer we could have Thanksgiving up here, because it was the day before Thanksgiving.’ Well, this gentleman, he was on the right hand side of the plane, he turned around and looked at me and smiled. I was one row behind him,” Almstad said.

The plane then landed and taxied to a remote part of the airport. According to Almstad, a refueling truck pulled up, along with a bus, and people came on board.

“Then a guy, I it was a man, came walking down the aisle with a white sack. To me, it looked like a pillow slip, and it had all these jagged points in it. And I remember the thought I had, that looks like bricks in it, or a bag of money, I thought,” Almstad said.

Almstad believes he may have seen the $200,000 ransom that Cooper had demanded, along with a parachute.

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Once the passengers were pulled off the plane, Almstad recalled, “…They took us into the terminal, and they took us upstairs, or somewhere. And there were FBI agents there, and they wanted to interview everybody.”

He didn’t have much to tell the FBI and didn’t even know it was a hijacking until he got off the plane.

Almstad said, “That was all there was to it. There was no conversation with him; he didn’t say anything to me. I went back to my seat, they let everyone off, and he jumped out, eventually.”

Jack Almstad might have had a better story to tell, if he weren’t such an avid reader, according to his wife Joyce. She said he practically read a book through much of the flight.

“It was probably a spy novel,” Joyce Almstad said.

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