A brutal drug war continues to rage south of the border where the violence is fueled by American guns.
An Action 4 News investigation reveals that gun traffickers are taking advantage of loopholes in federal laws.
Gun traffickers are using those loopholes to provide assault rifles and other weapons to drug cartels.
Tonight at 10 pm, the investigation also reveals how drug cartels use a network of recruiters and gun buyers.
The U.S. Bureau of Alcohol, Tobacco, Firearms & Explosives (ATF) has vowed to shut them down.
Ultimately, that gun is going to be used by someone for a crime of violence, said Jonathan Blais with the ATF in Harlingen. It's going to be used so that somebody can kill somebody else with it.
Drug cartel experts favor policy changes but second amendment advocates have different solutions.