Smugglers’ tunnel linking US and Mexico found

Authorities shut sophisticated drug passage under border into San Diego warehouseA deep tunnel snaking nearly 550 metres from Mexico under the border and into a San Diego warehouse is one of the most sophisticated underground drug smuggling passageways ever discovered, complete with electricity, ventilation and an electronic rail system, US federal authorities said .

The tunnel, which was shut down on Wednesday night after several weeks of surveillance, took approximately a year to build, the authorities said yesterday.

Three people were taken into custody yesterday, and federal agents seized 8 tonnes of marijuana and 147kg of cocaine they said was connected to the investigation.As security at the border , both at the ports of entry and between them, has heightened in recent years, drug cartels have increasingly sought other avenues, including tunnels, maritime smuggling and ultralight aircraft, to move drugs into the United States.

This was the fifth large-scale drug smuggling tunnel discovered in the San Diego area since 2010, the authorities said, and the eighth since 2006, when the Sinaloa drug cartel took firm control of the smuggling corridor along this section of the border.

"These cartels have spent years and tens of millions of dollars trying to create a secret underworld of passages so they can move large quantities of drugs," said Laura Duffy, the US attorney for the San Diego region.

Derek Benner, special agent in charge for Homeland Security Department investigations in San Diego, said sophisticated tunnels like the one found here - which required not only labourers to build but also architects and engineers, and could cost upwards of $1 million (€740,000) to construct - were an investment that only a well-financed cartel could afford to make.

He said the tunnel - like the two most recent "super-tunnels" in the region, which were discovered in late 2011 - had been shut down before any narcotics reached the market in the United States, which he called a major blow to the cartel. "This serves as yet another warning to these organizations that mistakenly believe that tunnels will be their ticket to success," Mr Benner said.

It was the first time cocaine had been seized in connection with a tunnel operation, the authorities said. "They're desperate," said William R. Sherman, special agent in charge for the Drug Enforcement Administration in San Diego. "We're starting to see them try to move cocaine through these tunnels, which we've never seen before. We're seeing them try to move cocaine through ultra-lights into the desert, which we've never seen before. And those are simply acts of desperation."

Tunnels have also been found around the Nogales area in Arizona, where cartels make use of underground drainage canals. But the San Diego-Tijuana corridor has remained popular for tunnel construction because the clay-like soil is easy to dig and less susceptible to cave-ins, Mr Benner said. In addition, the warehouse districts on both sides of the border offer cover for the drug smuggling operations.