Bureau of Alcohol, Tobacco, Firearms and Explosives
The Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) is a law enforcement agency within the United States Department of Justice mandated to enforce federal criminal laws concerning the unlawful use, manufacture, and possession of firearms and explosives, as well as acts of arson and bombings, and illegal trafficking of alcohol and tobacco products. The ATF also regulates the firearms and explosives industries via licensing.
The ATF works directly, and through partnerships with local law enforcement agencies to investigate and reduce crime.  The ATF employs approximately 5000 people across America and has a budget of nearly 1 billion dollars. Since 2001 the ATF has trained almost 6000 bomb technicians and investigators.