Authorities Monday discovered two pipe bombs attached to a storage tank containing 1 million gallons of alcohol, forcing the evacuation of businesses and residences within a half-mile radius.

The FBI, the U.S. Bureau of Alcohol, Tobacco and Firearms, the Virginia State Police bomb squad and an array of local units responded shortly after a worker found the bombs at the Allied Terminals Inc. in Norfolk, site of the nation's largest naval base, around 7:30 a.m.