High Quality Content by WIKIPEDIA articles! The National Tracing Center (NTC) of the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) is the sole firearms tracing facility in the United States. It provides information to provide federal, state and local law enforcement agencies with suspects for firearm crime investigations, detect suspected firearms traffickers, and track the intrastate and international movement of firearms. Congressional restrictions are in place to prevent the release of firearms trace information to anyone other than law enforcement agencies, however, this restriction does not apply to participating foreign countries or agencies. The only restriction is by Memorandum of Understanding (MOU) signed by the agency receiving eTrace software.