What the hell... did this really happen? I never heard of it so it must have went down BIW (before interwebs). This doesn't seem like it would be legal.Because government permits are difficult to obtain, there is a thriving market in smuggled handguns from the United States. One effort to control smuggling was Operation Forward Trace, conducted in the 1990s by the U.S. Bureau of Alcohol, Tobacco and Firearms. BATF agents examined federal gun registration documents (Form 4473) held on file at gun stores in southwestern states, and recorded the names and addresses of buyers - especially those with Hispanic names - who had purchased self-loading rifles or inexpensive handguns. BATF then contacted the purchasers, and demanded to know where the guns were.
Source: Mexican Gun Laws