THE United States Capitol was placed in lockdown today after shots were fired and a vehicle crashed into a security barricade near the White House.

The drama began close to the US Treasury building, just a block from the White House, when a woman with a child in her her car was stopped by police before she drove off at high speed towards Capitol Hill, hitting a security barrier and going through red lights along the way.

Police  fired shots and the car stopped. The woman was killed.

Police said the case was an isolated incident, unrelated to terrorism. 

One police officer was injured, but the extent of his injuries was not known.  The child in the car was uninjured, officials said.

About half an hour after the incident began, the security lockdown at the Capitol was eased and the doors reopened.