Federal authorities announced on April 20 that they discovered a sophisticated 800-yard drug tunnel -- including lights, ventilation, an elevator, and a rail system -- that went from San Diego, California, to Tijuana, Mexico (video below).
The tunnel began 300 yards inside the Mexican border, ran under the border, and went 500 yards north into the San Diego community of Otay Mesa, the Associated Press reports.
The U.S. end of the tunnel was found inside a pallet facility that was not doing any business, which drew suspicion from the Border Patrol, U.S. Attorney Laura Duffy said at a press conference on April 20, notes ABC 10 News.
There was "literally a hole in the ground hidden" by a "giant dumpster" that also served as a secret drug drop-off, Duffy said.
Authorities reportedly discovered about 14,000 pounds of marijuana and over 2,000 pounds of cocaine on the site.
There were numerous pallets and a "Otay Pallets -- We Buy Pallets" sign at the facility, which was allegedly doing "dry runs" that were observed by Border Patrol agents for months.
Six people were arrested on April 15 in San Diego and charged with crimes connected to drugs and the tunnel construction.
Dozens of tunnels have previously been discovered in warehouses near the U.S.-Mexico border in recent years as the warehouses serve as effective covers for digging equipment, according to the AP.
The accused in San Diego allegedly tried to disguise the dumpster as a legitimate trash receptacle, which it was not.
The "hole in the ground" under the dumpster led to a tunnel that was about 10 feet deep and 3 feet wide.
A commercial-grade elevator was found at the Mexico end of the tunnel that was hidden inside a "flophouse" filled with mattresses.
This tunnel was discovered after U.S. and Mexican authorities found another tunnel on Oct. 21, 2015, that connected the same communities.