The U.S. Department of Defense had a secret program to investigate reports of unidentified flying objects, and former Navy pilots in the program say they had a stunning encounter with a UFO in 2004.

The New York Timestells of the mission of Cmdr. David Fravor and Lt. Cmdr. Jim Slaight, who were in training over the Pacific Ocean off the coast of San Diego at the time. They got a strange call from a radio operator. The military had been tracking strange aircraft in the region for about two weeks, the operator said. Sometimes, these flying objects made sudden maneuvers, dove tens of thousands of feet or even hovered, according to the reports.

Asked to investigate, Fravor and Slaight eventually spotted one. About 40 feet (12 meters) long, it was hovering 50 feet (15 m) above the ocean, the Times report says. (Fravor added that the object appeared to be causing a sort of boiling or bubbles in the ocean, as the rest of the water looked calm.) [10 Alien Encounters Debunked]

Fravor descended, the object ascended to meet him and then it veered suddenly. "It accelerated like nothing I've ever seen, he said an interview with the Times, adding that he was "pretty weirded out." A few minutes later, the object disappeared, he said.

Fravor returned to his carrier ship, where people mocked him for what he saw, he told the Times. His superiors didn't look into the matter, and Fravor moved on to other things in his career, such as serving in the Persian Gulf as air support during the Iraq war.

Fravor's account includes a video — one of several recorded as a part of the program. The video shows a small object skirting from side to side and circling in view of the camera. The Times added that observers also underwent tests after their "encounters," to see how the experience had affected them.

"I can tell you, I think it was not from this world," Fravor added in a separate interview with ABC News. "I'm not crazy, haven't been drinking. It was — after 18 years of flying, I've seen pretty much about everything that I can see in that realm, and this was nothing close."

The news comes amid news that the U.S. government has been searching for UFOs, in secret, since at least 2007. While the Department of Defense says the program was shut down in 2012 due to a lack of funding, the Times further reported that this program is still active.

The program was called the Advanced Aerospace Threat Identification Program and had an annual budget of $22 million between 2008 and 2011. (By contrast, the budget of NASA as a whole was roughly $18.4 billion in fiscal year 2011.)

This isn't the first time that the government has looked into accounts of mysterious objects. In 2016, the Central Intelligence Agency released many previously classified documents that talked about unusual incidents, most of which occurred in the 1950s.

While the scientific evidence for UFOs is inconclusive, many people still want to believe. A 2012 survey said an estimated 80 million people in the U.S. believe in UFOs. Further, 1 in 10 respondents said they had seen UFOs for themselves.

In the Times interview, Fravor added that shortly after his encounter, he spoke with another pilot about what he saw. He told the pilot he had no idea what it was. "It had no plumes, wings or rotors and outran our F-18s," he told the Times, adding, "I want to fly one."

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