WASHINGTON (NewsNation) — Americans are pressing for answers after a rare congressional hearing on UFOs from the House Oversight Committee that featured three former high-level defense officials testifying to lawmakers on their experiences.

The historic hearing set up a new push by lawmakers as they investigate what the Pentagon knows — and may be hiding from the public.

During the hearing, former officials alleged that defense contractors are doing the work of covering up UFOs — along with the federal government.

NewsNation reached out to the largest defense contractors in the country, including Raytheon, Boeing, General Dynamics, and Northrop Grumman. They have not responded to a request to comment.

“Questions about UAPs are best addressed by the U.S. government,” a Lockheed Martin spokesperson told NewsNation.

Former federal agent Ben Hansen told NewsNation offered an explanation as to how a potential secret this big could be kept secret.

“The units of people working on this could be very small. I also know … this is circumstantial, I guess it’s not confirmed, but the way that this operates is that they will pull in people from across the country and different parts to work on it, where they’re not always perhaps housed in the same area,” said Hansen. “So one person will be working on one part of a team and they have no idea of the larger picture. And I have had whistleblowers come to me with little bits of the puzzle.”

Claims that defense contractors are in possession of UFOs have been around for years. This week’s congressional hearing, however, marked the first time those claims were read into the congressional record.