Drug Tunnel Found Linking San Diego and Tijuana Oct. 31, 2013 - A sophisticated drug tunnel that spanned the border and connected San Diego and Tijuana, Mexico, has been disovered by the U.S. Immigration and Customs Enforcement. The tunnel that officials said was just recently completely was built and was the latest tunnel to be uncovered beneath the border and was described as "highly sophisticated" by ICE spokeswoman Virginia Kice. The underground smuggling route was discovered by San Diego Tunnel Task Force, which consists of investigators from ICE, Homeland Security, Customs, Border Patrol and the Drug Enforcement Administration. Kice said that enforcement actions related to this discovery are still underway. In order to ensure the integrity of the ongoing investigation and the safety of those involved, we are not providing additional details at this time. San Diego is popular with tunnelers because its clay-like soil is easy to dig. Also, the U.S. side of the border is home to many warehouses. The tunnel uncovered Wednesday night was built about a block away from a similar tunnel that was uncovered in 2011, ABC News affiliate KGTV reported. That tunnel was stuffed with 32 tons of marijuana and was equipped with electric rail cars, lighting and ventilation. Another Tijuana-San Diego tunnel was revealed on Thanksgiving Day of 2010 that had 22 tons of pot.