Near the end of the movie just prior to the FBI questioning the "we were only there for technical support" guys, the caption on the screen gives the location as "FBI Headquarters". Although the building has an FBI shield displayed on it, the building shown is actually the Department of Housing and Urban Development (HUD) Headquaters located at 7th & "D" Streets. It has a distinct curved shape and the "saucers" in front. The J. Edgar Hoover Building does not. Having worked for both agencies I can tell you HUD is in southwest DC and the FBI is in northwest DC near Chinatown.