A brazen daylight assassination attempt against President Truman took place right on Pennsylvania Avenue with a shootout in front of Blair House. It was carried out by militant Puerto Rican pro-independence activists. White House Police officer Leslie Coffelt, was killed protecting the President.

Take a look back at Blair House, before it became government property in 1942. See a photo of the residence taken around 1918, when it was still a private home. Source: Library of Congress.