The mother of a woman shot dead by police after a car chase that began when she tried to breach a barrier at the White House said her daughter suffered from post-natal depression.

A woman driver was shot and killed by US police after trying to ram through a White House barricade with a young child in the car.

A woman driving a black Lexus tried to ram through a White House barricade then led police on a chase that ended in gunfire outside the Capitol.

Police say the U.S. Capitol has been put on a security lockdown amid reports of possible shots fired outside the building.