An attempt to ram the White House gates today resulted in a high speed chase to the Capitol and ended with shots fired and a female suspect dead, officials and sources said.
The gunfire sent senators and staffers scrambling inside the Capitol which was put under lockdown.
A child was found unhurt in the suspect's car, authorities said. After making an initial identification of the suspect, police are trying to confirm that the suspect is a 34-year-old woman from Stamford, Conn., with a history of mental health issues.
Police said there were no weapons found in the suspect's car.
The incident began when a vehicle rammed a barrier outside the White House at 15th Street and Pennsylvania Avenue NW. The car was chased to 2nd Street and Constitution Avenue NW, police said.
"[The suspect] circled monuments in front of Capitol Hill twice while being pursued. Then she headed toward the Capitol where Capitol Hill police and Secret Service opened fire and shot her," said Senate Sergeant at Arms Terry Gainer.
At one point, a group of at least five cops surrounded the woman's stopped car with their guns drawn. The suspect, driving a black two-door sedan, appeared not to heed their commands and sped off, nearly running over a couple of officers, as seen in a video obtained by ABC News.
With their pistols drawn, cops "were shouting at the driver," eyewitness Frank Schwing, a furloughed Commerce Department employee told ABC News. "At that point the driver put [the car] in reverse, drove back, and slammed into a cruiser."
The officers ran back to their cars and began chasing the woman again toward the Capitol.
The suspect's car rammed a Capitol Police vehicle and was stopped by an automated barrier near the Hart Senate Building, police said. Officers were authorized to shoot at the car.
Sources said the woman's vehicle is leased with out of state license plates.
"We heard pops that sounded like shots," 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 moments before it was placed on lockdown.
There is "no information this is related to terrorism or this anything other than an isolated incident," Capitol Police Chief Kim Dine told reporters.
A Capitol Police officer, who was initially reported shot, was later found to have been injured in a traffic accident involving an automated barricade during the pursuit.
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.