A Capitol police officer in Washington, DC, was killed and another was injured Friday outside Congress headquarters after a person hit them with a vehicle.
The suspect died after being detained and while being transferred to the hospital along with the officers.
Police told a news conference a few hours later that they had not found a link to terrorism and that the investigation was in its preliminary phase.
Two officers told NBC News, sister network of Noticias Telemundo, that after ramming two USCP officers, the driver jumped out of the car with a knife and was shot by Capitol police.
This occurred at the North Barricade vehicle access point along Independence Avenue.
The Capitol, home to the House of Representatives and the Senate, is under a state of alert.
Both the congressmen and their staff are prohibited from leaving their buildings while what happened is clarified.
Congress is in recess this week, so lawmakers had returned to their states and were not working on the building at the time of the attack.
A car crashed into a barricade in front of the Capitol, injuring two police officers.
A heavy police presence quickly descended on the area.
Multiple ambulances arrived as well as several helicopters.
First responders removed two stretchers from an ambulance and a helicopter landed on the east front of the Capitol.
A perimeter of several streets around has been closed to the public and the press.
A message sent to the Congressional offices read, "Due to an external security threat," "No entry or exit is allowed at this time. You can move inside buildings, but stay away from exterior windows and doors.
Yes is outside, seek shelter. "
Security on Capitol Hill has been beefed up with additional security measures and staff in place since a crowd of Trump supporters stormed the compound during the Jan.6 electoral vote count ahead of a joint session of Congress.
Senate Republican Minority Leader Mitch McConnell expressed concern about the injured officers in a message on Twitter.
"I am praying for the US Capitol police officers who were attacked on Capitol Hill. We are still learning what has happened. I thank all the USCP officers and first responders who are on the scene."
News in development.