India, June 23 -- US Border Patrol agents recently discovered and shut down a large drug-smuggling tunnel running from Tijuana, Mexico, into California. The tunnel, nearly 3,000 feet long, began under a house in Tijuana and ended near a warehouse in Otay Mesa, just south of San Diego, Daily Mail reported.

The tunnel was still being built when authorities found it in April, but it was already highly advanced. It had electrical wiring, lighting, a ventilation system, and even a rail system to move drugs. Officials believe the Sinaloa Cartel, once run by Joaquin "El Chapo" Guzman, is responsible for the tunnel. Though El Chapo is serving a life sentence in a maximum-security prison in Colorado, the cartel remains a powerful criminal group i...