"Jill [Biden] and I were heartbroken to learn of the violent attack at a security checkpoint on the US Capitol grounds", the president said in a statement.
The police officer killed in a vehicle attack at the United States Capitol was a native of Western Massachusetts who was a high school athlete.
Friday's attack on the U.S. Capitol that ultimately killed a Capitol Police Officer William Evans and a 25-year-old assailant Noah Green has raised questions about what kind of attacks are preventable, and what law enforcement could do to ensure a similar situation does not happen again. Green was shot and later died in the hospital, Pittman said during a news briefing.
Robert Contee, chief of the DC police department, told a news conference later that there was no longer an ongoing threat and the attack was not believed to be related to terrorism.
William Billy Evans joined the department in 2003 and was a member of its first responders unit.
"We saw the vehicle barriers perform the way they should".
Authorities installed a tall perimeter fence around the Capitol and for months restricted traffic along the roads closest to the building, but they had begun pulling back some of the emergency measures in recent weeks.
In a tweet Friday, Senate Minority Leader Mitch McConnell said, "Praying for the United States Capitol Police officers who were attacked at the Capitol". The White House said that the president had been receiving updates about the incident as investigation progresses.
Following the attack, the Capitol complex went under a lockdown, less than three months after a mob attacked the building and clashed with the police.
In 2013, officers with the Capitol Police and Secret Service fatally shot a woman inside her auto after she led them on a high-speed chase that began outside the White House.
Five people died in the January 6 riot, including Capitol Police officer Brian Sicknick, who was among a badly outnumbered force trying to fight off insurrectionists seeking to overturn the election.
Nearly 140 Capitol Police officers were wounded in that attack, including officers not issued helmets who sustained head injuries and one with cracked ribs, according to the officers' union.
Reports have also emerged identifying him as a follower of Nation of Islam leader, Louis Farrakhan, who has been described as an anti-Semite by anti-hate organization ADL.