TIJUANA, Mexico (AFP) ― Mexican authorities have unearthed a 600-meter drug smuggling tunnel beneath the U.S. border, the second such find in the same area this month.

The 4.5-meter-deep tunnel found on Tuesday was similar to another tunnel found on Nov. 16, and contained both lighting and transport carts, indicating the growing technical sophistication of the country’s powerful drug cartels.

“The tunnel was located after we were informed of it by U.S. authorities,” who had found the other end of the passage in nearby San Ysidro, California, Tijuana police chief Ricardo Garduno told AFP.

In Mexico, security forces who took part in the raid said three tons of marijuana were uncovered inside the tunnel.

But U.S. authorities said in a statement hours later that 32 tons of marijuana, worth 65 million dollars, were confiscated in the operation.

The U.S. Immigration and Customs Enforcement (ICE) service trumpeted the find as a major victory over Mexican drug cartels responsible for vast trafficking across the border into the United States.

The San Diego Tunnel Task Force, on the U.S. side of the border, said that six suspects had been arrested in the United States following a six-month investigation.

The entrance to the tunnel on the Mexican side was found some 100 meters from the local headquarters of the federal police, a military air base and a customs office, according to an AFP reporter.

On Nov. 16 U.S. authorities announced the discovery of a “major” drug smuggling tunnel under the border running some 400 meters and containing electricity and a ventilation system.

Some 45,000 people have been killed since 2006, when Mexico launched a major military crackdown against the powerful drug cartels that have terrorized border communities as they have battled over lucrative smuggling routes.