On May 20 , 1995 , primarily as a response to the Oklahoma City bombing of April 19 , 1995 , the United States Secret Service closed off Pennsylvania Avenue to vehicular traffic in front of the White House from the eastern edge of Lafayette Park to 17th Street . Later , the closure was extended an additional block to the east to 15th Street , and East Executive Avenue , a small street between the White House and the Treasury Building
Oklahoma City bombing
Oklahoma City bombing
White House