WASHINGTON (NewsNation Now) — “Textbook terrorism.” That’s how the mayor of Washington, D.C., described Wednesday’s siege on the U.S. Capitol.

Mayor Muriel Bowser, along with other D.C. officials, held a news conference Thursday to give residents an update after a mob of President Donald Trump’s supporters breached the Capitol’s perimeter and entered the building as Congress met to certify Joe Biden’s presidential election win.

Metropolitan Police Department Chief Robert Contee said 68 people were arrested in D.C. from Wednesday afternoon into Thursday morning. Of those arrested, 60 were men and eight were women and only one of the arrestees was from DC. Forty-one of the arrests occurred on Capitol grounds.

The majority of arrests were related to violations of the mayor’s 6 p.m. curfew, while others were arrested on charges related to carrying unlicensed or prohibited firearms.

It was not immediately clear how many people would be arraigned on Thursday.

Contee said more than 50 Capitol and Washington police officers were injured and several Capitol Police officers were hospitalized with serious injuries.

Steven Sund, chief of the U.S. Capitol Police, released a statement Thursday saying rioting protesters “actively attacked” police officers and “were determined to enter into the Capitol Building by causing great damage.”

“Police officers will support everyone’s right to express their First Amendment rights in this city. We will even risk our own safety to protect others’ right to do so,” D.C. Police Union said in a statement Thursday. “However criminal activity and violence is not a protected right and we will do everything within our legal authority to stop it. To be clear, we condemn, in the strongest possible terms, any and all violence used for such purposes, regardless of anyone’s politics.”

A Capitol Police officer shot and killed one person, who Sund identified as Ashli Babbitt, 35 of Huntington, Maryland. Sund did not identify the officer but said they would be placed on administrative leave pending an investigation.

Capitol Police identified three others who died during the unrest from medical emergencies: Rosanne Boyland, 35 of Kennesaw, Georgia, Kevin Greeson, 55 of Athens, Alabama and Benjamin Phillips, 50 of Ringtown, Pennsylvania.

Sund defended his agency’s response from criticism that officers did not stop the incursion. He said his agency “had a robust plan” for what he anticipated would be peaceful protests, but what occurred Wednesday was “criminal riotous behavior.”

Metropolitan police have released photos of dozens of persons of interest involved in violent protests, and are seeking the public’s help in identifying anyone who took part in the unrest. The department is asking anyone with information to either call (202) 727-9099 or text 50411.

While the number of people arrested is expected to grow, the initial number paled in comparison with the more than 300 people arrested by police following the June 1 protests in the District of Columbia related to the police killing of George Floyd.

In that incident, baton-swinging police and federal agents fired smoke canisters, flash-bang grenades and rubber bullets to drive protesters farther from the White House, enabling Trump to walk across Lafayette Square to historic St. John’s Church.

Late on Wednesday, the FBI also asked the public to submit tips, such as images, videos and other information, to help agents identify people who were “actively instigating violence.”

Bowser also extended a public emergency declaration for 15 days, an action she said will allow her to restrict peoples’ movements around the city if necessary.

Democrat President-elect Joe Biden is slated to take the oath of office on Jan. 20, 13 days from Thursday.