The military courthouse on the edge of Fort Hood has been transformed into a fortress.
It's surrounded by hundreds of stacked freight car-sized shipping containers, and by tall barriers designed to protect it against the impact of a bomb blast.
Tight security measures are in place at the Texas Army post and neighboring city of Killeen as jury selection is to start Tuesday in Maj. Nidal Hasan's court-martial.
The Army psychiatrist faces execution or life without parole if convicted in the 2009 shootings that left 13 dead and nearly three dozen wounded.
Two years ago a bomb attack was thwarted in Killeen. Some say the community may once again be targeted by Hasan's supporters.
In Killeen, authorities are placing "If you see something, say something" posters in businesses.