Authorities find massive drug-smuggling tunnel between Tijuana and San Diego

U.S. authorities on Monday announced the discovery of a major drug smuggling tunnel — running about the length of six football fields — from Mexico to a warehouse in an industrial area in the U.S.

The secret passage from Tijuana to San Diego featured rail and ventilation systems, electricity and reinforced walls, authorities said. It was discovered near San Diego's Otay Mesa border crossing in an area where more than a dozen other sophisticated tunnels have been found in the last two decades.

U.S. authorities said it was unknown how long the tunnel had been operating and what amount of drugs, if any, got through undetected. They seized 1,762 pounds of cocaine, 165 pounds of meth and 3.5 pounds of heroin in connection with the investigation.