The cost-cutting team gained access to the organization’s headquarters on Monday, despite officials arguing the Trump administration does not have the authority to gut the institute, the organization’s chief security officer, Colin O’Brien, told Fortune.

O’Brien said DOGE’s attempt to access the organization amounted to a “sustained effort over multiple days” that deployed “a range of tactics to gain entry.”

“It was unlike anything I have experienced in my professional career,” he said.

In a video shared online, D.C. police can be seen outside the institute’s headquarters in the Foggy Bottom neighborhood on Monday evening. O’Brien said USIP had contacted the police after DOGE tried to gain access to the building without permission.

In a statement shared with media on Monday, the organization’s former CEO, George Moose, said: “DOGE has broken into our building.”

He called the events “an illegal takeover by elements of the executive branch of a private non-profit.”

The organization has been in a standoff with Elon Musk’s cost-cutting team for several days, which escalated on Monday when DOGE staffers forced their way into the organization’s headquarters.

Congressman Don Beyer said the organization had been “stormed by DOGE, with the support of the D.C. police.” He said employees had been forced out and authorities had “picked the lock” on the Moose’s door and forced him to exit the building.

“This is not a federal agency, this is an agency that does not report to Donald Trump,” he said. “It’s a congressionally charted non-profit, and, like thousands of non-profits it gets some federal funding but that’s all subject to review by Congress, not the president of the United States.”

Beyer said he tried to gain access but was denied.

Representatives for the White House did not immediately respond to a request for comment from Fortune, made outside normal working hours.

In a statement on X, DOGE wrote: “Mr. Moose denied lawful access to Kenneth Jackson, the Acting USIP President (as approved by the USIP Board). @DCPoliceDept arrived onsite and escorted Mr. Jackson into the building. The only unlawful individual was Mr. Moose, who refused to comply, and even tried to fire USIP’s private security team when said security team went to give access to Mr. Jackson.”

Trump takes aim at foreign aid

Officials at the U.S. Institute for Peace have argued the Trump administration does not have proper authority to gut the organization since it’s not part of the executive branch.

According to its website, the U.S. Institute of Peace is a nonpartisan, independent organization committed to safeguarding U.S. interests by working to prevent violent conflicts and mediate peace agreements internationally.

The Trump administration removed most of the board of the U.S. Institute of Peace, per the AP, and replaced Moose as acting president with Kenneth Jackson, a State Department official who was involved in the dismantling of USAID, with the help of the remaining board members: Secretary of State Marco Rubio, Defense Secretary Pete Hegseth, and Peter A. Garvin, the president of the National Defense University.

The move appears to be part of a broader effort to dismantle the U.S.’s foreign aid programs.

Speaking to reporters after leaving the building, Moose said: “It was very clear that there was a desire on the part of the administration to dismantle a lot of what we call foreign assistance, and we are part of that family.”

Moose also said the organization had been in contact with DOGE since last month and had tried to explain its independent status.