WASHINGTON (AP) — Angry supporters of President Donald Trump stormed the U.S. Capitol on Wednesday in a chaotic protest aimed at thwarting a peaceful transfer of power, forcing lawmakers to be rushed from the building and interrupting challenges to Joe Biden’s Electoral College victory.

Trump issued a restrained call for peace and told supporters they had to “go home.” Earlier he had egged them on to march to Capitol Hill. The Pentagon said about 1,100 District of Columbia National Guard members were being mobilized to help support law enforcement at the Capitol.

Wednesday’s ordinarily mundane procedure of Congress certifying a new president was always going to be extraordinary, with Republican supporters of Trump vowing to protest results of an election that they have insisted was reversed by fraud. But even the unusual deliberations, which included the Republican vice president and Senate majority leader defying Trump’s demands, were quickly overtaken.

In a raucous, out-of-control scene, protesters fought past police and breached the building, shouting and waving Trump, Confederate and American flags as they marched through the halls. One person was reported shot at the Capitol, according to a person familiar with the situation and was said to be in critical condition. She has since died.

The protesters abruptly interrupted the congressional proceedings in an eerie scene that featured official warnings directing people to duck under their seats for cover, and put on gas masks after tear gas was used in the Capitol Rotunda.

With the crowds showing no signs of abating, Trump tweeted, “Please support our Capitol Police and Law Enforcement. They are truly on the side of our Country. Stay peaceful!”

Senators were being evacuated. Some House lawmakers tweeted they were sheltering in place in their offices.

Though some Republicans were behind the challenge to Biden’s 306-232 Electoral College victory, Senate Majority Leader Mitch McConnell sought to lower tensions and argued against it. He warned that the country “cannot keep drifting apart into two separate tribes” with “separate facts.”

McConnell declared, “The voters, the courts and the states all have spoken.”

But other Republicans, including House GOP leaders among Trump’s allies were acting out the pleas of supporters that attended his huge Wednesday rally up Pennsylvania Avenue outside the White House to “fight for Trump.”

“We have to fix this,” said Rep. Steve Scalise of Louisiana, the GOP whip.

The last-gasp effort is all but certain to fail, defeated by bipartisan majorities in Congress prepared to accept the November results. Biden is to be inaugurated Jan. 20.

Still, Trump vowed that he would “never concede,” and said, “We will never give up.”