We know about Mexico's strict gun laws for civilians. And we know that more than two-thirds of firearms Mexican authorities had traced earlier this year came from the United States.
Here's an anecdotal look at the weapons smuggling process. A 20-year-old Mexican national was arrested this weekend at the port of entry in San Luis, Ariz. From the Associated Press:
Authorities say a man has been arrested for attempting to smuggle empty assault weapon magazines out of the U.S. into Mexico.<br><br>[Customs and Border Protection] say they discovered 80 ammunition magazines for AK-47 assault rifles in his vehicle.
The ATF notes that criminals used rifles more than any other type of gun, especially the AK-47 and AR-15 variants.
The AR-15 is similar to the .223 Bushmaster semiautomatic rifle used in Friday's school shooting in Newtown, Conn.
