FILE - In this May 20, 1995 file photo, a flag soars above the White House in Washington, as construction workers place traffic barricades on the north sidewalk of Lafayette Park across from the White House. President Bill Clinton ordered the immediate closing of Pennsylvania Avenue in front of the White House to all but pedestrian traffic because of concern for security, an administration official said. The Secret Service is boosting security outside the White House following an embarrassing security breach in which an intruder with a knife scaled the White House fence, dashed across the lawn and made it all the way inside before agents managed to stop him. (AP Photo/Mark Wilson)