DALLAS (AP) — A Texas woman said Monday that she's suing a federal agency to force the return of a film shot by her grandfather that shows a portion of the 1963 assassination of President John F. Kennedy.

Gayle Nix Jackson, who lives in the Fort Worth area, is seeking $10 million in compensation for the film shot by Orville Nix on Nov. 22, 1963.

In the days after the killing, he gave the film to the UPI news agency with the understanding that after 25 years it would be returned to the family. However, it was obtained by the Warren Commission and another federal panel that investigated the shooting and assassin Lee Harvey Oswald.

It's not clear where the original copy may be but Nix Jackson believes it's in the possession of the National Archives and Records Administration because most materials that were part of the federal inquiry were forwarded to the NARA. The lawsuit says the agency has told Nix Jackson it does not have it. An agency spokeswoman declined to comment Monday.

The Sixth Floor Museum at Dealey Plaza says a film shot by Abraham Zapruder has greater historical value because it shows all of the shooting, as opposed to Nix's film and two others that capture part of the assassination.

Nix Jackson said her grandfather's film was shot from Dealey Plaza. She said it shows Zapruder across the street and the grassy knoll from where some witnesses thought they heard at least one shot fired.

It's incomprehensible that authorities would lose "an important piece of historical evidence," said Nix Jackson, whose lawsuit was filed Saturday in federal court in Washington, D.C.

"I can understand little clerical issues," she said. "I don't' understand the loss of evidence like this."

Nix filmed the presidential motorcade as it entered the plaza, but he didn't know he had captured the shooting until the photo lab that processed his film told him later.

The film sequence includes first lady Jackie Kennedy climbing onto the trunk of the limousine, and Secret Service agent Clint Hill jumping onto the vehicle, according to the lawsuit.

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