uschools/iStockBy IVAN PERIERA, ABC News

(WASHINGTON) — At least one person was shot and rushed to a hospital after supporters of President Donald Trump who rallied outside the U.S. Capitol clashed with police officers and breached the building, forcing a lockdown with members of Congress inside.

The protesters, some of who were seen wearing body armor, made their way up the steps around 2:15 p.m. ET, pushing through barricades, officers in riot gear and other security measures put in place in anticipation of the protest.

A woman was shot inside the Capitol and seriously injured, sources tell ABC News. A source familiar with the situation said DC Fire EMS is transporting a woman in critical condition to a local hospital.

It’s unclear what led to the shooting or if law enforcement was involved. Images showed officers with weapons drawn.

As of 5:32 p.m. the Capitol was still occupied.

After repeated calls from leaders on both sides of the aisle to call off his supporters, the president released released a video message on Twitter at 4:17 p.m. telling his supporters to go home. In the same video, he continued to push baseless, false claims about the election.

“I know you’re in pain, I know you’re hurt. We had an election that was stolen from us,” he said, repeating a false claim in the 1-minute pre-recorded video. “But you have to go home now.”

Twitter labeled the video with a warning, “This claim of election fraud is disputed, and this Tweet can’t be replied to, Retweeted, or liked due to a risk of violence.”

The tweet came just as Trump’s successor, Vice President Joe Biden, held a news conference to address the situation. He called on Trump to tell his supporters to stop.

“This is not dissent, it’s disorder. It’s chaos. It borders on sedition. And it must end now. I call on this mob to pull back and allow the work of democracy to go forward.

The entire D.C. National Guard has been activated to help, and several other law enforcement groups, including the Federal Protective Service, Secret Service, Virginia National Guard, and Arlington, Virginia, Police Department, are responding to assist the U.S. Capitol Police.

White House press secretary Kayleigh McEnany said around 3:40 p.m., the National Guard was on its way. House Speaker Nancy Pelosi requested the National Guard’s help to secure the Capitol, according to a source.

The clashes began as Trump and his allies held a rally earlier in the day pushing the Senate to not certify the election for President-elect Joe Biden. Once inside the Capitol, protesters moved freely and shouted chants while waving “Trump 2020” flags.

“Due to the violent behavior towards the police officers there and their intent on gaining access to the Capitol, a riot was declared,” D.C. Metro Police Chief Robert Conte told reporters at a news conference.

According to reports, at least one protester was in the dais of the Senate chamber and some were going door to door demanding, “Where the f— are they?” They were also banging on the doors, according to reports.

One of the protesters was photographed carrying a congressional lectern.

Around 4:15 p.m., the U.S. Bureau of Alcohol, Tobacco, Firearms and Explosives and Capitol Police were investigating a suspicious item close to the Republican National Committee headquarters building on First Street.

As the Trump supporters stormed the building, law enforcement officers inside instructed elected officials, staff and journalists to shelter in place. In a bulletin sent to Capitol staff later in the afternoon, Capitol Police ordered people to lock their doors, remain quiet and silence their electronics.

“If you are in a public space, find a place to hide or seek cover,” the bulletin read.

U.S. Rep. Jim Himes, D-Conn., tweeted, “Police have asked us to get gas masks out as there has been tear gas used in the rotunda.” U.S. Sen. Jeff Merkley, D-Ore, tweeted that the Electoral College ballots were rescued from the floor.

“If our capable floor staff hadn’t grabbed them, they would have been burned by the mob,” he tweeted.

West Virginia Sen. Joe Manchin told reporters that the Senate intends to finish certifying the election tonight.

Manchin told reporters he believes that they will be able to continue debate in the Capitol building. He said that being in the secure holding room with other Senators had a “way of bringing us together.”

“We’re going to finish tonight,” Manchin said. “These thugs are not running us off.”

Around 3:20 p.m., the Senate chamber was reportedly secured and officers were in the process of pushing protesters down from the second and third floor of the rotunda, according to police.

During the rally earlier in the day, Trump said he would not concede and called on the supporters to march up to the Capitol. He promised the crowd he would be with him, but did not follow-up his promise and went back to the White House.

“We will not let them silence your voices. We’re not going to let it happen,” Trump said to a cheering crowd.

As the breaching started, Trump tweeted that Vice President Mike Pence “didn’t have the courage to do what should have been done to protect our Country and our Constitution,” and “USA demands the truth!”

Trump tweeted at 2:39 p.m., “Please support our Capitol Police and Law Enforcement. They are truly on the side of our Country. Stay peaceful!”

At 3:13 p.m., he tweeted, “I am asking for everyone at the U.S. Capitol to remain peaceful. No violence! Remember, WE are the Party of Law & Order – respect the Law and our great men and women in Blue. Thank you!”

At 3:35 p.m., Pence, who was escorted out of the building, also pleaded on Twitter for the Trump supporters to stop.

“The violence and destruction taking place at the US Capitol Must Stop and it Must Stop Now. Anyone involved must respect Law Enforcement officers and immediately leave the building,” he tweeted.

U.S. Sen. Mitt Romney told reporters who were with him in a secure position, “This is what the president has caused today, this insurrection.” Romney had been accosted by a Trump supporter at an airport Tuesday.

U.S. Senate Democratic Leader Chuck Schumer and House Speaker Nancy Pelosi released a joint statement around 3:50 p.m. and called on Trump “to demand that all protestors leave the U.S. Capitol and Capitol Grounds immediately.”

Former members of Trump’s inner circle also condemned the president for not doing enough to stop his supporters. Former White House Chief of Staff Mick Mulvaney tweeted that the president’s tweets were not enough.

“He can stop this now and needs to do exactly that. Tell these folks to go home,” he tweeted.

Washington, D.C., Mayor Muriel Bowser issued a citywide curfew beginning at 6 p.m. and ending Thursday at 6 a.m.

“During the hours of the curfew, no person, other than persons designated by the Mayor, shall walk, bike, run, loiter, stand, or motor by car or other mode of transport upon any street, alley, park, or other public place within the District,” the mayor’s office said.

During a news conference later in the afternoon, Bowser called the protests “shameful, unpatriotic” and “unlawful.”

“The Metropolitan Police Department has been deployed to assist the United States Capitol police in restoring order to the Capitol. And our chief of police will lead the command to clear the Capitol building and establish a perimeter around the Capitol,” she said.

ABC News’ Allie Pecorin, Trish Turner Allison Pecorin, Jack Date, Ben Siegel and Luke Barr contributed to this report

This is a developing story. Please check back for updates.

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