SMITHTOWN, N.Y. (AP) _ When Pierre Salinger charged that TWA Flight 800 was brought down by ``friendly fire,'' he bolstered it with a claim that an Air France jet had to swerve wildly to avoid a missile that same night.

But just as the TWA missile theory was quickly dismissed as ``utter nonsense,'' the chief FBI agent on the case called the Air France claim ``pure fiction, something out of a Star Wars episode.'' And Air France said radar data, cockpit communications and the flight report filed by the crew showed nothing out of the ordinary.

``We studied everything in the skies that night and Air France made no such maneuver, nor did any other aircraft,'' FBI Assistant Director James Kallstrom said Tuesday.

Kallstrom for the first time Wednesday cast some doubt that a criminal act was to blame for the crash. Investigators have looked at three scenarios: mechanical malfunction, bomb or missile

``We have a large percentage of the airplane and we see no evidence of a bomb or missile,'' he said. ``From the standpoint of logic, it is becoming less likely that a bomb or missile caused this crash.''

But Kallstrom cautioned that 5 percent of the plane remained unrecovered and said that evidence could emerge that points to a bomb or missile.

Salinger, a former ABC correspondent and press secretary for President Kennedy, twice put investigators on the defensive with theories he got secondhand.

The TWA theory was based on a two-page document that has been floating around the Internet for months, and which investigators say is worthless.

The Air France tale, told in a Nov. 9 CNN interview, came from a man Salinger met who said he was on an Air France flight that took off from Kennedy Airport for Paris minutes after Flight 800. The man said that a few minutes into the flight, the pilot made a wild right turn.

Salinger said the passenger _ whose name he doesn't know _ told him that when he went into the cockpit and asked what happened, the pilot said: ``We can't go into that region. They're sending missiles up there. It's very dangerous!''

Investigators and airlines agreed the latest rumor would be impossible because there was no U.S. missile training in the area on the night of the July 17 TWA explosion. They said that the closest Navy ship was 180 miles away, out of missile range, and that the military aircraft in the area did not carry armed missiles.

Further, FAA spokesman Mark Hess said there were no restrictions that night affecting commercial airplanes.

``If there were sudden maneuvers or a missile, you can rest assured that it would definitely have ended up in the pilot's log,'' said Bruce Haxthausen, Air France spokesman. ``But it wasn't there. That is absolutely definite.''

Kallstrom said Air France officials also told the FBI there was ``absolutely nothing unusual on the flight and the plane did not make any movement like those described by Salinger.''

``We verified this through the FAA, which reviewed both the radar track and cockpit communications,'' Kallstrom said. ``I hope this puts Mr. Salinger's latest theory to bed.''