Manuel Alejandro Ramirez Rodriguez -- of Cuauhtmoc, Chihuahua, Mexico -- was arrested on December 18th.
Customs and Border Patrol agents say that Rodriguez, 22, seemed nervous when he was questioned while at the Presidio Port of Entry around 5 PM on December 18th.
Rodriguez's 1997 Chevrolet pickup Truck was then selected for a secondary inspection.
Drug sniffing dog "Basa" alerted agents to the pickup truck's gas tank.
Agents quickly found two metal boxes in the gas tank, which reportedly contained 125 pounds of compressed marijuana.
The seized drugs reportedly had a street value of $100,000.
Agents immediately seized the marijuana and arrested Rodriguez.
Rodriguez has now been turned over to the custody of U.S. Immigration and Customs Enforcement special agents.