It was not an accident.
That's the extraordinary claim being made about TWA flight 800, the jetliner that blew up off the coast of Long Island in 1996.
Former NTSB investigator Hank Hughes helped with the painstaking reconstruction of the aircraft after the disaster. He is one of the experts featured in a new TV documentary that claims the tragedy was caused by: "one or more explosions outside the aircraft."
"It was a flawed investigation," said Hughes. "We found penetration of what appeared to be projectiles. There were nitrates found, evidence of an explosive."
Tom Stalcup, one of the movie's producers, told INSIDE EDITION, "An external detonation caused this crash and we have proof of that. We have evidence that that occured. We stopped short of saying, if it was a missile, who may have fired it? Was it a friendly fire missile, was it a terrorist missile? We don't get into that."
All 230 people aboard the JFK-to-Paris flight were killed. Coast Guard footage shows the grim search for the remains of the passengers and crew.
Many witnesses said at the time they had seen a trail of light, possibly from a missile moments before the plane blew up.
But the NTSB determined that an electrical fault in a fuel tank triggered the explosion.
The new documentary claims that the true cause of the crash was covered up.
"There was just many, many instances of strange and unusual, inappropriate behavior," said Hughes.
The documentary is likely to be met with skepticism by many. The NTSB investigation into the disaster took four years, making it perhaps the most extensive in U.S. aviation history. A separate FBI probe also found no evidence of criminal activity.
James Kallstrom led the original FBI investigation. INSIDE EDITION's Megan Alexander spoke to him by phone and asked, "Was there a coverup?"
"I don't know of any coverups. Certainly there was no coverup on the FBI's part, and I don't believe there was on NTSB either."
The documentary airs on the cable channel Epix July 17th, the 17th anniversary of the disaster.