A Texas man bought dozens of guns from licensed dealers in the state before illegally reselling at least 16, U.S. officials say. Twelve were traced to crimes committed in America. The other four were traced to crimes in Canada.

The case of the 31-year-old, indicted last month on charges that could see him jailed for years, illustrates the leading role the Lone Star State now plays in the smuggling of guns used for violence in Canada, and how firearms tracing can help combat that trade.

Canadian police chiefs say such cases also show the limits of their government's domestically focused policies to fight gun violence, such as a freeze on handgun purchases, when it has the world's largest civilian gun market on its doorstep.