At least one U.S. military serviceman has been arrested for allegedly planning another attack on Ft. Hood, Fox News has learned exclusively. According to an Army source, one AWOL soldier is in the custody of the Killeen Police Department near Ft. Hood. He was not captured on base. According to another source, two other U.S. soldiers were also arrested earlier today when they were found in possession of weapons and explosives. Fox News has obtained the names of three possible suspects, but is currently withholding that information.