SAN DIEGO (AP) — Authorities have announced the discovery of an underground smuggling tunnel on Mexico’s border, running the length of a football field on U.S. soil to a warehouse in an industrial area. The cross-border tunnel from Tijuana to the San Diego area was built in one of the most fortified stretches of the border, illustrating the limitations of former President Donald Trump’s border wall. Authorities have found about 15 sophisticated tunnels on California’s border with Mexico since 2006. Hallmarks of the passageways include lighting, ventilation, railway tracks and hydraulic lifts. Many tunnels, including the one announced Monday (May 16, 2022), are in San Diego’s Otay Mesa industrial area.