If the truth is out there, the US Congress wants to know.

The House of Representatives convened a landmark panel on unidentified anomalous phenomenon (UAPs), known more colloquially as UFOs, on Wednesday, in the most serious acknowledgement yet that mysterious sightings deserve scrutiny at the highest levels of government.

US lawmakers were "not bringing little green men or flying saucers into the hearing… we're just going to get to the facts," Republican Tim Burchett said at the beginning of the meeting. Yet the testimony at times strayed into the unknown.

Over the course of two hours, three witnesses shared their encounters with objects that defied physics and told of pilots afraid to speak up, biological material recovered from crafts, and alleged retaliation against whistleblowers. All acknowledged that anomalous phenomena were a potential national security threat.

The hearing produced no serious bombshells - nor a confirmation of alien life - but the fact that the witnesses received a major hearing before Congress was notable in and of itself. Lawmakers and witnesses alike used the panel to demand greater transparency around UAPs from the military.

Retired US Navy commander David Fravor once again recounted his encounter with a "tic-tac" shaped UAP in 2004 that moved in a way that baffled aviators, footage of which was released in 2017 and publicly verified by the US Navy two years later.

"The technology that we faced was far superior than anything that we had, have today, or are looking to develop in the next 10+ years," Mr Fravor said.

David Grusch, an ex-Air Force intelligence officer, hinted that government officials had suppressed information and punished whistleblowers, but claimed he could not elaborate further in public due to classification laws.

In one notable exchange, Nancy Mace, a South Carolina Republican, asked Mr Grusch elaborate on what he knew about non-terrestrial bodies.

She asked him if "biologics" were recovered from any crafts retrieved by the government.

Referencing his previous media interviews, Mr Grusch responded that "biologics came with some of these recoveries".

Were they human or non-human? Ms Mace asked.

"Non-human, and that was the assessment of people with direct knowledge on the programme I talked to," Mr Grusch responded. During a different line of questioning, he confirmed he had never personally seen an alien body.

Witnesses also called for an official reporting process for military personnel or members of the public to report unexplained sightings

"We need a system where pilots can report without losing their jobs," said Ryan Graves, executive director of Americans for Safe Aerospace.

Congress seemed eager to grant that request by the end of the session.

"UAPs, whatever they be, may pose a serious threat to our military and our civilian aircraft, and that must be understood," Robert Garcia, a California Democrat, said. "We should encourage more reporting, not less on UAPs. The more we understand, the safer we will be."

While both Republican and Democratic lawmakers took the subjects seriously, a few expressed scepticism that extraterrestrial activity was afoot.

Eric Burlison, a Missouri Republican, attempted to poke holes at the concept that pilots saw alien objects. He said he found it difficult to believe beings who could travel billions of miles to reach us would be "incompetent" enough to crash on Earth.

He asked whether any of the UAPs could actually be craft created by military contractors, or belong to secret agency programmes that other government entities had hidden.

Washington's public embrace of UFOs as a policy issue has moved with the same astonishing velocity as the mysterious objects, going from shadowy backroom meetings with a handful of enthusiasts to a full-blown, televised panel that received the same serious questioning as any other national security matter.

In 2017, the issue burst into the open when The New York Times reported the existence of a secret Pentagon programme to investigate unidentified aerial phenomenon.

The programme was backed by former Senate Majority Leader Harry Reid, who represented the state of Nevada - and therefore, Area 51.

The New York Times, as well as an organisation called To The Stars Academy of Arts and Science, also published three videos showing unexplained encounters with UAPs. Since that time, the US military has gradually acknowledged these encounters while declining to speculate about their origins.

Investigating UFOs, now known to many as UAPs, has become a rare bipartisan issue in Congress. Lawmakers of both parties have called for investigations and military transparency. In 2022, the House Intelligence Committee held a hearing about the secretive Pentagon programme. Nasa held a public hearing on the matter in June.

Both former presidents Barack Obama, a Democrat, and Donald Trump, a Republican, have addressed the issue in public interviews. National Security Council spokesman John Kirby said he was open minded.

"What we believe is that there are unexplained aerial phenomena that have been cited and reported by pilots - Navy and Air Force," Mr Kirby said. "We don't have the answers about what these phenomena are."

In a rarity for a televised congressional hearing, nearly all the lawmakers focused their questioning on the subject at hand on Wednesday.

"Many Americans are deeply interested in this issue," Jared Moskowitz, a Florida Democrat, said. "And it shouldn't take the potential of nonhuman origin to bring us together."