The US Drug Enforcement Administration discovered a tunnel used for drug, weapon, and human smuggling under the U.S.-Mexico Border in the small Arizona town of San Luis over the weekend. Thursday, the DEA held a press conference revealing the initial findings from this ongoing investigation. Michelle Faust from member station KAWC in Yuma, AZ has the story.

MICHELE FAUST: DEA investigators had been watching an empty business in a shopping center just northwest of the San Luis Port of Entry since January. A drug bust during a traffic stop lead to a search warrant Saturday morning where agents discovered the tunnel. Fifty feet under the U.S.-Mexico Border, the tunnel is 750 feet long, 6 feet tall and 3 feet wide. It's equipped with electricity and a ventilation system, something the agency rarely sees. Doug Coleman of the DEA explains.

DOUG COLEMAN: I can't think that I've seen too many more that had this amount of work and this amount of sophistication behind it. Most of the time what we find here in Arizona is just dug into the dirt or used through the sewer system in Nogales.

FAUST: U.S. Officials say this is the first fully functional tunnel found in Yuma County, but had not been in use for long. It is believed to have been used by the Sinaloa cartel.