Catherine Austin Fitts, who served as the assistant secretary of Housing and Urban Development for Housing between 1989 and 1990, made the shocking allegations during an appearance on former Fox News host Tucker Carlson’s podcast, although there is no concrete evidence to support her claims.

Fitts, 74, who is originally from Philadelphia, cited research by Michigan State University economist Mark Skidmore, who released a report in 2017 stating that he and a team of scholars had uncovered $21 trillion in “unauthorized spending in the departments of Defense and Housing and Urban Development for the years 1998-2015.”

At the time, Skidmore noted that he first began investigating the unreported spending after he heard Fitts “refer to a report which indicated the Army had $6.5 trillion in unsupported adjustments, or spending, in fiscal 2015.”

“Given the Army’s $122 billion budget, that meant unsupported adjustments were 54 times spending authorized by Congress. Typically, such adjustments in public budgets are only a small fraction of authorized spending,” the report noted.

Initially, Skidmore said he thought Fitts had made a mistake, stating that he assumed she had meant to say $6.5 billion, not trillion.

“So I found the report myself and sure enough it was $6.5 trillion,” he said.

According to Fitts, who worked as an investment banker before joining Bush’s administration, that money was used to fund the development of what she described as an “underground base, city infrastructure and transportation system” that has been kept hidden from the public.

“One of the things I’ve looked at in the process of looking at where all this money is going is the underground base, city infrastructure, and transportation system that’s been built,” she said.

“We have built an extraordinary number of underground bases and, supposedly, transportation systems.”

She told Carlson that she spent two years researching where the $21 trillion had gone, alleging that she uncovered evidence that there are 170 secret facilities in the U.S. alone, explaining that she and a team of investigators combed through “all the data and all the allegations on underground bases” in order to make a “guess” as to how many might exist.

Additionally, Fitts alleged that several of these bases are located beneath oceans—not just underground.

“We systematically went through and tried to guess estimate our guess—this is totally a guess—of how many underground bases [there are], both underground in the United States, but also underground under the ocean around the United States.

“And our estimate was 170 with a transportation network connecting them,” she said.

“We systematically went through and tried to guess estimate our guess—this is totally a guess—of how many underground bases [there are], both underground in the United States, but also underground under the ocean around the United States.

When Carlson asked what the “purpose” of these underground bases is, Fitts responded that they would be used if a “near-extinction event” was believed to be on the horizon.

However, she added that she believes these so-called bases could also be used by the government to carry out “secret” projects, such as a “secret space program.”

Carlson responded by claiming that he actually knew “a contractor who worked on one in Washington, D.C.,” stating: “I remember him telling me about a power box, like a transformer box, on Constitution Avenue. … He told me [that] was actually the exit, the egress from the White House.

“And I thought, that’s kind of crazy in the middle of this big city where I live … you could build something like that without me knowing it.”

Carlson said he had always assumed that those kinds of bases were only located in D.C.—and that they were meant specifically for some kind of “nuclear war,” to which Fitts responded: “Some of it is. It’s preparation for catastrophe.”

As for how these alleged cities and facilities are powered, Fitts said she believes the government has found a way to generate breakthrough energy that she believes is being used to keep them going.

“I’m convinced that this energy exists. If you look at a lot of the really fast ships, flying around the planet, they’re not using classical electricity,” she claimed.