Sophisticated 'Super' Drug Tunnel Between California and Mexico Discovered

The tunnel was 2,600 feet long.

Isaias Enriquez-Acosta, 53, and Isidro Silva-Acosta, 27, were charged Thursday with unlawful conspiracy to import a controlled substance and conspiracy to use border tunnels and passages.

Agents found a hole in the floor near a warehouse in Otay Mesa -— a city south of San Diego -- that led to a shaft descending almost 32 feet down in the ground. The shaft connected to an underground passageway, which included lighting, ventilation and a rail system, leading to the U.S.-Mexico border.

“We see a super tunnel open for business once every year or so,” U.S. Attorney Laura Duffy told ABC News today. “Just when they think they’re ready to move, we put it out of business.”

The Tunnel Task Force conducted a six-month investigation that revealed the 2,600-foot long tunnel, to be one the largest uncovered along the southern border in recent years.

Since 2010, federal authorities have found more than 75 smuggling tunnels, mostly in California and Arizona.