A narco tunnel has been found on the US-Mexico border, but it's not clear who's responsible for it

Tijuana San Diego narco tunnel entranceTijuana PressA Mexican soldier guards the entrance to a suspected narco tunnel discovered in Tijuana, not far from the US border, October 20, 2016.

Official from the US and Mexico confirmed last week that a tunnel connecting Tijuana and San Diego had been found, one of dozens of such tunnels discovered along the border over the last five years.

An ice store, called La Hielera del Aeropuerto, concealed the tunnel’s entrance, located roughly 330 yards from the US border on Boulevard Cuauhtémoc Norte, and the passage reportedly had its exit in the US in a store in San Diego, according to a report from Tijuana Press.

The entrance was found just west of Tijuana’s A.L. Rodríguez International Airport. An official report has yet to be released, but authorities suspected that there were at least 5 tons of marijuana located within the tunnel and buildings at either end.

A source with the public-safety secretariat of Baja California told The San Diego Union-Tribune that the tunnel had been in operation, and that an anonymous tip had guided state police and Mexican soldiers to it.

The US attorney’s office told a local Fox affiliate that no federal charges had been filed in relation to the tunnel.

Tijuana Mexico San Diego narco tunnel drug smugglingChristopher Woody/Google MapsThe entrance to the suspected narco tunnel was discovered just a few hundred yards from the US-Mexico border.

Neighbours said the business began operating a year and half or two years prior, and that prior to that, the lot was empty, according to Tijuana Press. While it was open, locals told Tijuana Press that the business didn’t seem out of the ordinary.

At least six narco tunnels have been discovered in the area, Tijuana Press reported, including one a half-block from the tunnel discovered last week.

More than 75 smuggling tunnels have been found along the US-Mexico frontier, many of them in California and Arizona, over the last five years, and the tunnel is the 13th large-scale smuggling passage found in operation on the California-Mexico border since 2013.

La Hielera del Aeropuerto was just a few blocks from the border fence, which divides northern Tijuana from the Otay Mesa area of San Diego.

That area is both logistically and geographically favourable to subterranean smuggling efforts: Warehouse space on both sides of the border has expanded rapidly since the 1990s, and commercial activity — vehicle traffic, trucks loading and unloading, and construction — are common, and help conceal the excavation of tunnels and the comings and goings of smugglers.

Moreover, the soil in the area is a type of clay that’s “self-supporting and as workable as wax.” This clay is sturdier than normal soil, which reduces the need for bracing in the tunnels.

The area was the location of the longest such tunnel discovered on the Mexico-California border: A zig-zagging 874 yard passage uncovered in April that led to the seizures of 2,240 pounds of cocaine and more than 7 tons of marijuana.

It’s not yet clear the people or group responsible for construction of this tunnel.

The Sinaloa cartel has been dominant on the ground in Tijuana since the 2000s, but in recent months mounting evidence — particularly a growing body count — indicates that the ascendant Jalisco New Generation cartel is clashing with the Sinaloa cartel in and around Tijuana, which is valuable to smugglers because of its proximity to the US.

Despite the frequency with which these tunnels are uncovered, they are actually hard to uncover, as ground-penetrating radars are not effective in the soil in the area and because of other factors that help obscure illicit activity. Given that, the latest tunnel discovery is unlikely to be the last.

“There’s nothing we can do about it and it’s nothing new in the area,” a local businessman told Fox 5 San Diego.

“They are going to continue,” a local woman told Tijuana Press.

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