WASHINGTON (WJZ) — A group of pro-Trump extremists breached the U.S. Capitol Wednesday afternoon as lawmakers were convened to certify the Electoral College votes from the 2020 presidential election, sending lawmakers into lockdown.

Some fought past police and breached the building, shouting and waving Trump and American flags as they stormed through the halls.

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Michael Greenberger, with the University of Maryland Center for Health and Homeland Security and a professor at the University of Maryland Francis King Carey School of Law, called this an act of “domestic terrorism.”

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“Low and behold, today we have terrorists, but they’re domestic terrorists,” Greenberger said.

“The inauguration has been put in danger, the Electoral College approval has been put in danger,” he added. “We have never seen the capitol, the Senate floor, the House floor being made a target of people wielding weapons,” he added.

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Greenberger said these actions are crimes that are prosecutable with the intention of overturning the democratic election of a president of the United States, noting it’s a classic act of insurrection and indictable.

He said he believes the political consequences are going to be dramatic.

“The criminal acts involved – storming the capitol, using weapons is not just a criminal act of itself, but it’s a criminal act designed principally to undo the presidential election,” Greenberger said.

“Under normal circumstances, you would think the Capitol Police would be able to prevent this from happening,” he added. “But I don’t think anybody could envision the depth and intensity of the rioting that took place.”

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Greenberger said he wouldn’t be surprised to see Maryland begin their own criminal investigation into who caused this.