In the first public congressional hearing on what are commonly known as UFOs in more than 50 years, a senior Defense Department intelligence official said on Tuesday that the Pentagon is committed to determining the origins of what the government calls “unidentified aerial phenomena.”

Two top U.S. defense intelligence officials testified before a House intelligence subcommittee 11 months after a report detailing more than 140 cases of unidentified aerial phenomena, or UAPs, observed by U.S. military pilots since 2004.

“We know that our service members have encountered unidentified aerial phenomena, and because UAP pose potential flight safety and general security risks, we are committed to a focused effort to determine their origins,” Ronald Moultrie, US defense undersecretary for intelligence and security, said at the hearing.

Scott Bray, the deputy director of naval intelligence, was the other official who testified.

The more popular term, UFO, for unidentified flying object, has long been associated with the concept of alien spacecraft, which was not mentioned in the UAP presentation last June. Instead, the emphasis was on the potential implications for US national security and aviation safety.

However, the report did include some UAPs previously revealed in Pentagon-released video footage of enigmatic airborne objects with speed and maneuverability exceeding known aviation technology and lacking any visible means of propulsion or flight-control surfaces.

That report was a nine-page “preliminary assessment” compiled by the Director of National Intelligence and a Navy-led task force formed by the Pentagon in 2020.

In his opening remarks, subcommittee chairman Andre Carson said it was critical for the Pentagon to remove the stigma associated with unidentified aerial object sightings, which he said had long discouraged military pilots from reporting them so they could be analyzed.

“True, UAPs are unexplained. They are, however, real “Carson stated.

Except for one sighting attributed to a large deflating balloon, the defense and intelligence analysts who prepared the assessment offered no conclusions about the origins of any of the 144 sightings included in it.

The Navy task force behind the paper was replaced in November by the Airborne Object Identification and Management Synchronization Group, a new Defense Department agency.

Following the public hearing, Moultrie and Bray were scheduled to testify behind closed doors.

While drawing no conclusions, last year’s report stated that the UAP sightings are unlikely to have a single explanation.

According to the report, more data and analysis are needed to determine whether they represent some exotic aerial system developed by a secret US government or commercial entity, or by a foreign power such as China or Russia. Senior US officials told reporters ahead of the report’s release last year that defense and intelligence analysts have yet to rule out an extraterrestrial origin for any UAP case, though the paper itself avoided any explicit reference to such possibilities.

Nonetheless, the report marked a watershed moment for the US government, which had spent decades deflecting, debunking, and discrediting reports of unidentified flying objects and “flying saucers” dating back to the 1940s.

The session will be the first open congressional hearing on the subject since the United States Air Force ended the inconclusive Project Blue Book UFO program in 1969.

During its 17-year run, Blue Book compiled a total of 12,618 UFO sightings, 701 of which involved objects that were officially deemed “unidentified.” However, the Air Force later stated that it found no evidence of a national security threat or extraterrestrial vehicles.

In 1966, nearly a decade before becoming president, then-Rep. Gerald Ford of Michigan, who was the House Republican leader at the time, organized a hearing in response to scores of witness accounts of strange glowing lights and large football shapes at low altitude near Dexter, Michigan, which an Air Force official famously explained away as “swamp gas.”