Major drug tunnel found on US-Mexico border in California

Before you go, we thought you'd like these...
Possible Drug Tunnel Found in Otay Mesa

SAN DIEGO (AP) -- Mexican authorities said Thursday they seized about 10 tons of marijuana in an elaborate tunnel with a rail car system that extended well into San Diego and was designed to smuggle drugs into the U.S. from Tijuana.

The discovery on Wednesday marks one of the longest and more sophisticated clandestine tunnels found on the U.S.-Mexico border.

SEE MORE: World's most wanted drug lord injured while fleeing a raid on his mountain hideout

The passage was 9 feet deep and about 2,600 feet long — about three-quarters of that distance in Tijuana and the rest in San Diego. It was lit, ventilated and built with metal beams to prevent collapse.

It was unclear whether any drugs got through the tunnel or if it had an exit yet in the U.S.

Lauren Mack, a spokeswoman for U.S. Immigration and Customs Enforcement, declined to comment.

It was also unclear which drug trafficking organization began the engineering feat.

The region is largely controlled by Mexico's Sinaloa cartel, whose leader Joaquin "El Chapo" Guzman escaped from a maximum-security prison in Mexico in July through an elaborate tunnel.

Click through to see more of the elaborate tunnel:

18 PHOTOS
El Chapo Tunnel Escape Route
See Gallery
Major drug tunnel found on US-Mexico border in California
Federal Police officers stand guard inside a half-built house where drug lord Joaquin "El Chapo" Guzman made his escape through a tunnel from the Altiplano maximum security prison in Almoloya, west of Mexico City, Thursday, July 16, 2015. A widespread manhunt that included highway checkpoints, stepped up border security and closure of an international airport failed to turn up any trace of Guzman after he escaped through an underground tunnel in his prison cell. (AP Photo/Marco Ugarte)
A motorcycle adapted to a rail sits in the tunnel under the half-built house where according to authorities, drug lord Joaquin "El Chapo" Guzman made his escape from the Altiplano maximum security prison in Almoloya, west of Mexico City, Thursday, July 16, 2015. A widespread manhunt that included highway checkpoints, stepped up border security and closure of an international airport failed to turn up any trace of Guzman after he escaped through an underground tunnel in his prison cell. (AP Photo/Marco Ugarte)
A Mexican Federal Police officer crouches inside the tunnel where according to authorities drug lord Joaquin "El Chapo" Guzman made his escape from the Altiplano maximum security prison in Almoloya, west of Mexico City, Thursday, July 16, 2015. Two Mexican lawmakers say at least 18 minutes had elapsed from when Mexico's most prized prisoner slipped into a mile-long tunnel Saturday night and when authorities became aware. An official with the National Security Commission said he would try to confirm the figure, but did not think it was that much time. (AP Photo/Marco Ugarte)
Mexican Federal Police officers stand guard at the exit of a tunnel where according to authorities drug lord Joaquin "El Chapo" Guzman made his escape from the Altiplano maximum security prison in Almoloya, west of Mexico City, Thursday, July 16, 2015. Two Mexican lawmakers say at least 18 minutes had elapsed from when Mexico's most prized prisoner slipped into a mile-long tunnel Saturday night and when authorities became aware. An official with the National Security Commission said he would try to confirm the figure, but did not think it was that much time. (AP Photo/Marco Ugarte)
A Mexican Federal Police officer crouches as he walks through the tunnel that according to authorities drug lord Joaquin "El Chapo" Guzman used to make his escape from the Altiplano maximum security prison in Almoloya, west of Mexico City, Thursday, July 16, 2015. Two Mexican lawmakers say at least 18 minutes had elapsed from when Mexico's most prized prisoner slipped into a mile-long tunnel Saturday night and when authorities became aware. An official with the National Security Commission said he would try to confirm the figure, but did not think it was that much time. (AP Photo/Marco Ugarte)
Federal Police officer stands in the tunnel where according to authorities drug lord Joaquin "El Chapo" Guzman made his escape from the Altiplano maximum security prison in Almoloya, west of Mexico City, Thursday, July 16, 2015. Two Mexican lawmakers say at least 18 minutes had elapsed from when Mexico's most prized prisoner slipped into a mile-long tunnel Saturday night and when authorities became aware. An official with the National Security Commission said he would try to confirm the figure, but did not think it was that much time. (AP Photo/Marco Ugarte)
This photo shows the shower area where authorities claim drug lord Joaquin "El Chapo" Guzman, slipped into a tunnel to escape from his prison cell at the Altiplano maximum security prison, in Almoloya, west of Mexico City, Wednesday, July 15, 2015. (AP Photo/Eduardo Verdugo)
The photo shows the interior of the cell occupied by drug lord Joaquin "El Chapo" Guzman, from where authorities claim he escaped via a tunnel in his shower cell, at the Altiplano maximum security prison, in Almoloya, west of Mexico City, Wednesday, July 15, 2015. In the top left corner is a security camera. (AP Photo/Eduardo Verdugo)
A Mexican authority climbs a ladder to exit the tunnel that according to authorities, drug lord Joaquin "El Chapo" Guzman used to escape from the Altiplano maximum security prison in Almoloya, west of Mexico City, Thursday, July 16, 2015. Two Mexican lawmakers say at least 18 minutes had elapsed from when Mexico's most prized prisoner slipped into a mile-long tunnel Saturday night and when authorities became aware. An official with the National Security Commission said he would try to confirm the figure, but did not think it was that much time. (AP Photo/Marco Ugarte)
A Mexican authority climbs up a ladder leading to the exit of the tunnel that was used by Mexican drug lord Joaquin "El Chapo" Guzman, to escape from the Altiplano maximum security prison in Almoloya, Mexico, Tuesday, July 14, 2015. (AP Photo/Marco Ugarte)
The photo shows the opening of a tunnel, authorities claim was used by drug lord Joaquin "El Chapo" Guzman, to escape from inside his cell at the Altiplano maximum security prison, in Almoloya, west of Mexico City, Wednesday, July 15, 2015. (AP Photo/Eduardo Verdugo)
A journalist reports from the exit of the tunnel that according to authorities, drug lord Joaquin "El Chapo" Guzman used to escape from the Altiplano maximum security prison in Almoloya, west of Mexico City, Tuesday, July 14, 2015. A widespread manhunt that included highway checkpoints, stepped up border security and closure of an international airport failed to turn up any trace of Guzman after he escaped through an underground tunnel in his prison cell. (AP Photo/Eduardo Verdugo)
A journalist climbs a ladder to get out of the tunnel that according to authorities, drug lord Joaquin "El Chapo" Guzman used to escape from the Altiplano maximum security prison in Almoloya, west of Mexico City, Tuesday, July 14, 2015. A widespread manhunt that included highway checkpoints, stepped up border security and closure of an international airport failed to turn up any trace of Guzman after he escaped through an underground tunnel in his prison cell. (AP Photo/Eduardo Verdugo)
Journalists exit the tunnel where according to authorities drug lord Joaquin "El Chapo" Guzman made his escape from the Altiplano maximum security prison in Almoloya, west of Mexico City, Tuesday, July 14, 2015. A widespread manhunt that included highway checkpoints, stepped up border security and closure of an international airport failed to turn up any trace of Guzman after he escaped through an underground tunnel in his prison cell. (AP Photo/Eduardo Verdugo)
A motorcycle adapted to a rail sits in the tunnel under the half-built house where according to authorities, drug lord Joaquin "El Chapo" Guzman made his escape from the Altiplano maximum security prison in Almoloya, west of Mexico City, Tuesday, July 14, 2015. A widespread manhunt that included highway checkpoints, stepped up border security and closure of an international airport failed to turn up any trace of Guzman after he escaped through an underground tunnel in his prison cell. (AP Photo/Eduardo Verdugo)
The exit of the tunnel that according to authorities was used by Mexican drug lord Joaquin "El Chapo" Guzman, to escape from the Altiplano maximum security prison is seen in Almoloya, Mexico, Tuesday, July 14, 2015. A widespread manhunt that included highway checkpoints, stepped up border security and closure of an international airport failed to turn up any trace of Guzman after he escaped through an underground tunnel leading from his prison cell's shower area. (AP Photo/Mario Vazquez de la Torre)
In this photo provided by Mexico's attorney general, authorities inspect the exit of the tunnel they claim was used by drug lord Joaquin "El Chapo" Guzman to break out of the Altiplano maximum security prison in Almoloya, west of Mexico City, Sunday, July 12, 2015. A massive manhunt is underway after Guzman, escaped from the maximum security prison through the tunnel that opened into the shower area of his cell, the country's top security official announced. (Mexico's Attorney General's Office via AP)
of
SEE ALL
BACK TO SLIDE
SHOW CAPTION +
HIDE CAPTION

Mexican police said in a press release about the drug tunnel that 16 people were detained on suspicion of drug trafficking and had told authorities that they had ties to a criminal group that operates in the state of Jalisco — an apparent reference to the Jalisco New Generation cartel, which controls that part of western Mexico.

The people detained were 21 to 50 and were caught off-guard when Mexican authorities arrived at a Tijuana warehouse with a search warrant, police said. No shots were fired.

The drugs were wrapped in 873 packages covered with plastic and tape, police said.

Dozens of tunnels have been found along the U.S.-Mexico border in recent years — the most sophisticated equipped with hydraulic lifts and electric rail cars.

The San Diego-Tijuana region is popular because its clay-like soil is easy to dig with shovels and pneumatic tools, and both sides of the border have warehouses that provide cover for trucks and heavy equipment.

More from AOL.com:
Donald Trump shares bizarre tweet asking about Iowa, corn, and brain 'issues'
Ben Carson topples Donald Trump in new Iowa poll
The next Republican debate field is set -- here's who's in and who's out

Read Full Story

People are Reading