YUMA, AZ (3TV/CBS5) -- Special agents with Homeland Security Investigations (HSI) have discovered what they call "the most sophisticated [drug] tunnel in U.S. history" outside Yuma.
The smuggling tunnel begins in San Luis, Arizona, then stretches past the Mexican border into a neighborhood in Mexico.
Agents say the tunnel is 3 feet wide and 4 feet high and is highly sophisticated. It's equipped with a fully-developed ventilation system, water lines, electrical wiring, a rail system and extensive reinforcement.
"Homeland Security Investigations and our esteemed law enforcement partners swiftly and effectively worked together to uncover and dismantle a cross-border tunnel for smuggling purposes into the United States," said Scott Brown, HSI special agent in charge in Phoenix. "Despite the international pandemic, HSI and our law enforcement colleagues remains resilient and committed to pursuing dangerous criminal trans-border smuggling activities along the southwest border."
In mid-July, federal agents discovered a sinkhole along the U.S.-Mexico border between the primary and secondary border fences. HSI special agents responded to the area and observed that the sinkhole was in line with the area of an ongoing tunnel investigation.
On July 27, with the help of federal partners, border patrol agents began drilling near the sinkhole. During the drilling, pieces of wood and water hoses were found underground. Agents also noticed what appeared to be a void below.
A specialized camera was then deployed 25 feet underground to investigate the gap, and agents discovered the tunnel.
“This appears to be the most sophisticated tunnel in U.S. history, and certainly the most sophisticated I’ve seen in my career,” said Carl E Landrum, acting chief patrol agent, Yuma Sector.
San Luis is located in the southwest corner of the state, south of Yuma and right at the Arizona-Mexico border.