An attempt to ram the White House gates ended with shots fired at the U.S. Capitol, senators put under lockdown and a female suspect dead, sources told ABC News.
A Capitol police officer was also reported shot, sources said.
"We heard pops that sounded like shots," said Sen. Bob Casey, D-Pa told ABC News.
"We heard shots. They told us to get behind a car," Sen. Sherrod Brown, D-Ohio, said as he re-entered the Capitol building just smoments before it was placed on lockdown.
Secret Service pursued a suspect from the White House to the Capitol. One agent in a marked Secret Service vehichle was injured when the car in which he was chasing the suspect was upended by one of the Capitol's electronic barricades as it rose out of the ground.
An initial alert to lawmakers and staffers came around 2:25 p.m. A half hour later at 2:55 p.m., the lockdown was lifted. The Supreme Court was also briefly closed following reports of gunfire.
"Close, lock and stay away from external doors and windows. Take annunciators, emergency supply kits and escape hoods; and move to your office's assigned shelter in place location or the innermost part of the office away from external doors or windows," Capitol Police told Congressional staffers staffers in an email.
The Capitol this week is the center of a contentious political battle over an ongoing government shutdown.