Story highlights

Six people have been charged with drug trafficking

The tunnel features ventilation systems, lights and even a large elevator

It leads to a closet in a Tijuana home

CNN  — 

A drug-trafficking tunnel nearly half a mile long underneath the California-Mexico border was discovered by federal agents, the U.S. Attorney’s Office said Wednesday.

Two tons of cocaine and seven tons of marijuana, worth nearly $22 million, were seized by federal agents who believe this to be the “longest cross-border tunnel ever discovered.”

A border first: Smugglers buy U.S. land, build house to hide tunnel, feds say

Federal officials say the tunnel stretches from Tijuana, Baja California, Mexico to Otay Mesa, about 500 yards north of the U.S.-Mexico border.

The 800-yard tunnel route begins at a house in Tijuana, Mexico, and ends in the Otay Mesa neighborhood of San Diego.

Agents were hot on the tail of the alleged drug traffickers after they noticed a commercial truck deliver an industrial dumpster filled with wood scraps to an outdoor industrial lot; days later, agents discovered this to be an entryway into the tunnel.

The tunnel was furnished with ventilation systems, lights and even a large elevator that led into a closet inside the Tijuana residence, officials said.

Feds raid drug ‘super tunnel’ with railway on U.S.-Mexico border

The tunnel exit on the U.S. side is a 3-foot-diameter hole that was covered by an industrial dumpster.

“On the surface, few would ever suspect that traffickers were moving multiton quantities of cocaine and marijuana worth tens of millions of dollars in such an unassuming way, through this rabbit hole in the ground, in full view of the world around it,” said U.S. Attorney Laura Duffy in the release.

The six people were arrested in San Diego and charged with various drug trafficking charges, police said.

“This case is a strong reminder of the vulnerabilities that exist along the Southwest border,” said Hunter Davis, director of air operations for Customs and Border Protection, Air and Marine Operations.

Since 2006, 13th large-scale operational drug smuggling tunnels have been discovered along the California border, federal agents said.

CNN’s Sheena Jones contributed to this article.