Barba was arrested on Feb. 16, coincidentally one day after the murder of Zapata in Mexico. Federal sources tell Local 2 the ATF's Houston division was informed on Feb. 25, 2011, that the gun purchased in Beaumont by Riendfliesh was found at Zapata's murder.

"The drug cartels operate on both sides of the border," U.S. Rep. Ted Poe said. "People who think drug cartel crime stops at the border really are living in Never Neverland."

Poe said this entire investigation highlights a point has been trying to impress upon some of his colleagues in Washington for years.

"It is more than a border security issue," said Poe. "It's a national security issue. That's what this is all about, the drug cartels coming into the United States any way they can."

Poe said he will continue pushing for more federal resources to be devoted to the southern border.