Last December, the New York Times published an expose on a secretive Defense Department program that had been investigating reports of unidentified flying objects—UFOs—for nearly a decade. Among the reports analyzed by the Advanced Aerospace Threat Identification program was a video that had been released a few months earlier that depicted a white, oval object that was chased by two F/A-18F fighter jets off the coast of California in 2004. The object, which has since become known as the “Tic Tac UFO” in alien hunting circles, was moving at high speeds and had no apparent means of propulsion.

"It takes off like nothing I've ever seen,” retired Navy pilot David Fravor, who was flying one of the fighter jets that day, told the New York Times. “One minute it's here, and off it's gone.”

Now, a local investigative news team in Las Vegas obtained a 13-page document [ PDF] prepared for the military that analyzes what happened that day in 2004. The investigation was led by George Knapp, a journalist who made a name for himself in the 80s for substantiating parts of a story peddled by the prominent UFOlogist Bob Lazar, who claimed to have worked at Area 51.

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The report describes how the Anomalous Aerial Vehicle (AAV) seen by the two F18 pilots were able to “descend ‘very rapidly’ from approximately 60,000 feet down to approximately 50 feet in a matter of seconds.” Moreover, they would “hover or stay stationary on the radar for a short time and depart at high velocities and turn rates.”

The report details the advanced characteristics of the AAV, which had been sighted by another aircraft carrier off the coast of California “three separate times” in the days before it was intercepted by the F18s as seen in the video. The aircraft was capable of “advanced acceleration, aerodynamic and propulsion capability,” wasn’t susceptible to the military’s radar capabilities, “possibly demonstrated the ability to ‘cloak’ or become invisible to the human eye or human observation,” and “possibly demonstrated a highly advanced capability to operate undersea completely undetectable by our most advanced sensors.”

The report notes how one of the senior crew members on the aircraft carrier with 17 years experience in the military said the AAV exhibited characteristics of a ballistic missile. The reason the aircraft carrier’s radar system was unable to track the object was because it was set to monitor conventional aircraft so when the object appeared on the radar it was dropped as a false target. “If the radar were set up in a mode for Ballistic Missile tracking, they likely would have had the capability to track the AAV,” according to the report.

When the F18 pilots were deployed to investigate the phenomenon, they had a hard time tracking and getting information about the AAV on the radar. Nevertheless, certain characteristics of the radio signals picked up by the pilots were strange.

“It was obvious there was something out there and the fighters were taking it seriously,” the report reads.

According to the report, one of the pilots dispatched to investigate the object reported seeing a disturbance in the otherwise calm ocean. The pilot reported that the “disturbance appeared to be 50 to 100 meters in diameter and close to round” and “reminded him of images of something rapidly submerging from the surface like a submarine or ship sinking.”

“It is possible that the disturbance was being caused by an AAV, but that the AAV was ‘cloaked’ or invisible to the human eye,” the report concludes. “At no time did they consider the AAV a threat to the battle group. Finally, they had never seen anything like this before and never again.”