With the U.S. Capitol in the background, authorities stand by newly placed fencing around the Capitol grounds the day after violent protesters loyal to President Donald Trump stormed the U.S. Congress in Washington, Thursday, Jan. 7, 2021.

Evan Vucci / AP Photo

A U.S. Capitol Police officer, who was assaulted during the insurrection at the Capitol, died at approximately 9:30 p.m. Thursday evening, according to a statement from the USCP. He was 42.

Officer Brian Sicknick, who joined the USCP in 2008, served in the department’s first responder’s unit and was responding to the attack on the Capitol when he was injured. He returned to his division office and collapsed before being taken to a local hospital, the department reported.

It is the fifth death associated with Wednesdays’ violent events. Ashli Babbitt, an Air Force veteran who embraced the QAnon conspiracy theory, was shot and killed by a Capitol Police officer inside the building, and three other people died of still-to-be-explained “medical emergencies,” according to officials.

Sicknick’s death will be investigated by the Metropolitan Police Department’s homicide branch, the USCP, and the Department of Justice. Attorney General Jeffrey Rosen said in a statement that the Justice Department “will spare no resources in investigating and holding accountable those responsible.”

More than 50 officers from the Capitol Police and Metropolitan Police force were injured on Wednesday, U.S. Capitol Police Chief Steven Sund said in a statement.

The federal law enforcement force has come under immediate and heavy criticism for the lapse in preparation. Sund has already tendered his resignation, as has House Sergeant of Arms Paul Irving.

In the early hours of Friday morning, officers lined the front of the Capitol in silence paying respects to the fallen officer, WUSA9’s Mike Valerio reported.

Virginia Rep. Don Beyer said in a statement that Sicknick “made the ultimate sacrifice” and “like others before him who died in defense of the people’s representatives, he deserves to lie in state.”

“I mourn his loss, and send my deepest condolences to his family,” Beyer continued. “His murder multiplies the pain of this dark moment for our nation, and those who brought about this awful crime must be prosecuted and brought to justice.”

Editor’s Note: An earlier version of this story was retracted. Its first version reported Sicknick’s death prematurely, relying on inaccurate early reporting from NPR. We deeply regret the confusion and the error.