The US secret service has found a bullet from a semi-automatic rifle that smashed a window at the White House, according to officials.
The service has been investigating a shooting that occurred near the White House on Friday.
Yesterday, the service discovered two bullets, one of which had smashed a window before being stopped by special anti-ballistic glass protecting the building's interior; the other round was found outside the building.
Shots were fired between two vehicles on Constitution Avenue, about half a mile from the White House, shortly after 9 pm on Friday.
Later the same evening, secret service officials discovered an AK-47 rifle in an abandoned car.
A US park police spokesman Sergeant David Schlosser, said police were still looking for a suspect, and had issued an arrest warrant for a Oscar Ramiro Ortega, in connection with the shooting.
Police believe he has been in the Washington area for several weeks, Schlosser said. "We want to hear from Ortega. We want to hear his version as to what happened. This will help us fill in the blanks as to what actually occurred."
US President Barack Obama and Michelle Obama, were in California at the time of the shooting.
6,000 The approximate number of visitors the White House receives every day