Washington: UFO whistleblower, who claimed that the US government is secretly holding alien spacecraft, gave evidence to the Congress on Wednesday.

During a remarkable congressional hearing, former American intelligence official David Grusch revealed that the US government conducted a “multi-decade” programme aimed at collecting and reverse-engineering crashed unidentified flying objects (UFOs).

Grusch, who was in charge of investigating unexplained anomalous phenomena within a US Department of Defence agency until 2023, spoke before the House oversight committee in Washington, shedding light on the issue of alien life and technology, as reported by the Guardian.

This hearing, prompted by Grusch’s previous claims, attracted global interest and ignited discussions about the possibility of a government cover-up regarding UFOs.

In a statement, US Defense Department spokeswoman Sue Gough said investigators have not discovered “any verifiable information to substantiate claims that any programs regarding the possession or reverse-engineering of extraterrestrial materials have existed in the past or exist currently.”

Grusch said he was asked in 2019 by the head of a government task force on UAPs to identify all highly classified programs relating to the task force’s mission.

“I was informed in the course of my official duties of a multi-decade UAP crash retrieval and reverse engineering program to which I was denied access,” he said.

Grusch’s highly anticipated testimony before a House Oversight subcommittee was Congress’ latest foray into the world of UAPs — or “unidentified aerial phenomena,” which is the official term the US government uses instead of UFOs.

Asked whether the US government had information about extraterrestrial life, Grusch said the US likely has been aware of “non-human” activity since the 1930s.

Grusch said he became a government whistleblower after his discovery and has faced retaliation for coming forward. He declined to be more specific about the retaliatory tactics, citing an ongoing investigation.

“It was very brutal and very unfortunate, some of the tactics they used to hurt me both professionally and personally,” he said.

Rep. Glenn Grothman chaired the panel’s hearing and joked to a packed audience, “Welcome to the most exciting subcommittee in Congress this week.”

But members of both parties asked Grusch about his study of UFOs and the consequences he faced.

Pentagon officials in December said they had received several hundreds of new reports since launching a renewed effort to investigate reports of UFOs.