U.S. Rep. Diana DeGette on Wednesday called for the impeachment of President Donald Trump after an unprecedented attack on the U.S. Capitol, which was stormed by the president’s supporters while Congress was certifying Joe Biden’s election win.

“President Trump instigated a violent attack on our Capitol. He is a danger to our country.,” the Denver Democrat said.

“He should be impeached and removed from office immediately.”

Violent Trump supporters invaded the Capitol after the president egged on a raucous crowd at a rally near the White House earlier in the day, forcing the House and Senate to stop debating the formal certification of electoral votes and evacuate the chambers.

“We will never give up. We will never concede,” Trump told the crowd before urging his followers to march to the Capitol.

“Get rid of the weak Congress people,” he said, adding “get the weak ones out; this is the time for strength.”

Trump has denied for months that he lost the Nov. 3 election to Biden, floating groundless conspiracy theories and unfounded allegations of widespread fraud.

“Make no mistake: This was not a protest, it was an attempted coup,” DeGette tweeted. “I never thought I’d see the day that our own president would attempt to bring down our government because he lost an election.

“We will return to the floor as soon as possible to finish certifying the results of the electoral college and declaring Joe Biden and Kamala Harris the next president and vice president of the United States.”

Other Democratic lawmakers blaming Trump for inciting the rioters who swarmed the Capitol also called on Vice President Mike Pence to invoke the 25th Amendment, which could lead to removing Trump from office.

Florida Democratic Rep. Val B. Demings, a former police chief, recalled Trump’s words weeks ago to members of a white nationalist group to “stand back and stand by.”

“We have a criminal president who has incited violence. He wanted this. Our country cannot heal until he and his spineless enablers are held criminally accountable for their actions,” she tweeted. “Justice demands it.”

The Associated Press reported that legal experts said such charges would be possible but the likelihood was in question.

“Impeachment and criminal prosecution are not mutually exclusive,” former Justice Department watchdog Michael Bromwich tweeted. “More than enough evidence to prosecute Trump for treason, sedition, and incitement.”

The Associated Press contributed to this report.

UPDATE: Soon after this story posted, DeGette deleted an earlier tweet calling for Trump to be “impeached, removed from office and arrested immediately” and replaced it with a tweet saying Trump should be “impeached and removed from office immediately,” dropping the suggestion that the president be arrested. This story has been updated.