U.S. authorities on Wednesday announced the discovery of the longest smuggling tunnel ever found on the Southwest border, stretching more than three-quarters of a mile from a small industrial building in Tijuana, Mexico, into the San Diego area.
U.S. Customs and Border Protection said the tunnel featured an extensive rail/cart system, forced air ventilation, high voltage electrical cables and panels, an elevator at the tunnel entrance, and a complex drainage system.
“This one blows past (the second-longest),” said Lance LeNoir, a Border Patrol operations supervisor. “We never really thought they had the moxie to go that far. They continue to surprise me.”
Following the discovery in August, Mexican law enforcement identified the tunnel entrance and members of the San Diego Tunnel Task Force began mapping the tunnel from Mexico, the agency said.
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The tunnel extends a total of 4,309 feet. The next longest tunnel in the U.S. was discovered in San Diego in 2014. It was 2,966 feet long.
The newly discovered tunnel is about 5.5 feet tall and 2 feet wide and runs at an average depth of 70 feet below the surface, officials said.
Agents discovered several hundred sandbags blocking the suspected former exit of the tunnel in the Otay Mesa warehouse district within the U.S.
While there were no arrests, drug seizures or confirmed exit point in the United States, the length — more than 14 football fields — stunned authorities. It went under several warehouses in San Diego’s Otay Mesa area, where sophisticated tunnels have typically ended, and extended into open fields.
U.S. authorities say they are highly confident that the tunnel exited in San Diego at one time, based on its trajectory.
LeNoir, a veteran on a multiagency task force of tunnel investigators known as “tunnel rats,” said he made his way through about 50 feet of sugar sacks blocking the tunnel but couldn’t go any farther.
An incomplete offshoot of the tunnel that extended more than 3,500 feet suggested to authorities that smugglers plugged an initial exit point and were building another.
The suspected previous exit “became unsustainable for whatever reason, so they built a spur,” Border Patrol spokesman Jeff Stephenson said.
By federal law, U.S. authorities must fill the U.S. side of tunnels with concrete after they are discovered. Officials say that makes it unlikely that the tunnel disclosed on Wednesday had previously been found.
“The sophistication and length of this particular tunnel demonstrates the time-consuming efforts transnational criminal organizations will undertake to facilitate cross-border smuggling,” said Cardell T. Morant, acting special agent in charge of Homeland Security Investigations in San Diego.