San Diego Sector Border Patrol agents assigned to the Tunnel Interdiction Group discovered an unfinished cross-border narcotics smuggling tunnel stretching nearly 3,000 feet from a residence in the Nueva Tijuana neighborhood to beneath the Otay Mesa Port of Entry. The discovery in early April 2025 marked one of the longest incomplete tunnels ever found along the California-Mexico border, and investigators traced its origin to a foreign terrorist organization with what U.S. Customs and Border Protection described as “substantial resources.”
The tunnel extended more than 1,000 feet inside United States territory. When agents made their first entry, they found electrical wiring, overhead lighting, a forced-air ventilation system, and a rail-mounted cart track designed for moving large quantities of contraband. Multiple makeshift barricades had been placed inside the passage, apparently by tunnel workers attempting to slow agents from tracing the route southward back to its origin point in Tijuana.
Investigation and Arrests
Working with Mexican law enforcement, agents identified the tunnel’s starting point at a private residence in Nueva Tijuana. Because the tunnel was still under construction at the time of discovery, investigators believe it had not yet been used for active smuggling operations. The joint investigation led to 12 arrests on both sides of the border, with suspects facing federal charges related to conspiracy to import controlled substances and illegal tunneling under 18 U.S.C. 555, a law enacted specifically to criminalize cross-border tunnel construction.
Part of a Wider Pattern
Since the mid-1990s, approximately 95 cross-border tunnels have been found and decommissioned in the San Diego sector alone, most concentrated in the Otay Mesa industrial zone where warehouses and commercial buildings provide cover for tunnel entry points. The San Diego Tunnel Task Force – a multi-agency unit including HSI, DEA, Border Patrol, and the U.S. Attorney’s Office – continues to use ground-penetrating radar and seismic sensors to detect subsurface excavation activity. Residents in the Otay Mesa area who notice unusual construction noise, dirt hauling, or ventilation equipment at odd hours can report tips to the Border Patrol sector tip line at (619) 498-9900.