U.S. authorities have released dramatic footage showing the inside of a sophisticated cross-border drug smuggling tunnel stretching from Tijuana, Mexico, to Southern California. According to Homeland Security investigators, the tunnel ran nearly 2,000 feet beneath the U.S.-Mexico border and was equipped with reinforced walls, electricity, ventilation systems, and even a rail track used to transport narcotics. Officials say the tunnel's U.S. exit was hidden beneath a retail business near the Otay Mesa Port of Entry in San Diego and could be accessed through a concealed hydraulic lift. Show more Show less