Mexican police on Thursday announced that they have found a 800m long tunnel near the Tijuana border crossing with the US.
The tunnel, which ran under the border, was reported to belong to the drug cartel leader Joaquin Guzman, best known as ‘’El Chapo.’’
According to the officials, authorities found 12 tonnes of marijuana and arrested at least 16 people after discovering the longest cross-border tunnel.
Mexican cartels have been smuggling drugs to the US through underground tunnels for years.
The National Security Commission said the operation was carried out "without firing a single shot, surprising the suspected drug smugglers."
Many of the suspects, who are aged between 21-50, are from the northwestern state of Sinaloa. During their interrogation, they told the investigators that they packed and delivered drugs to the US for a criminal group operating out of the western Mexican state of Jalisco.
Guzman, Mexico's most wanted drug lord, escaped from prison for the second time in July through a mile-long tunnel.
Laura Duffy, the US attorney in San Diego said the tunnel was exposed by US federal agents, who have been monitoring the Mexican drug-smugglers for the past six months.
Duffy also said, federal agents conducted a raid on the US side of the tunnel on Wednesday, after observing a delivery of 2 tonnes of marijuana and six men were detained, two of the suspects were in court on Thursday facing charges of drug-smuggling.
Two Mexican government security officials, speaking on condition of anonymity to Reuters, stated that the passage belonged to drug lord 'El Chapo'.
Subterranean passageway stretching from Mexico to Otay Mesa was discovered in 2002. In the last decade, dozens of tunnels have been found along the 2,000 mile border, the latest tunnel had lighting, ventilation and a rail system for moving goods, authorities said.