U.S. and Mexican authorities on Thursday confirmed the existence of a clandestine cross-border tunnel between Tijuana and San Diego.
The tunnel's entrance was found near Tijuana's A.L. Rodríguez International Airport, said a source with Baja California's Public Safety Secretariat.
The source said that the tunnel had been in operation, and that an anonymous tip had led Mexican soldiers and members of the state police to its opening at an ice-making business some 300 yards from the U.S. border fence.
Mexican authorities since Thursday morning blocked off access to the business, La Hielera del Aeropuerto, located southwest of the airport on Boulevard Cuauhtemoc. It was unclear where the U.S. exit is located.
U.S. Immigration and Customs Enforcement Homeland Security Investigations released a statement Thursday afternoon confirming the discovery of a tunnel in the San Diego/Tijuana area, but did not disclose its location.
"In order to ensure the integrity of the ongoing investigation, HSI San Diego is not providing additional details at this time," the statement said.