Seal of the United States Bureau of Alcohol, Tobacco, and Firearms from when it was part of the Department of the Treasury.  The design is the same as the Treasury seal with an ATF inscription.
Extracted from PDF version of the 2002 ATF annual report (direct PDF URL [1]), and colorized according to the version on a late ATF home page before it was moved to the Department of Justice.
U.S. federal government