A 530 meter long drug tunnel has been discovered on the border between the United States and Mexico, according to the US judiciary.

The corridor led from Tijuana, Mexico, to San Diego, California, at a depth of up to 18 meters, according to the California prosecutor's office on Tuesday.

The tunnel was therefore equipped with "reinforced partition walls, a rail system, electricity and ventilation systems".

According to the authorities, criminal proceedings have been initiated against six suspects residing in the USA.

They should answer for the smuggling of almost 800 kilograms of cocaine.

In addition, 74 kilograms of methamphetamine and 1.5 kilograms of heroin were also confiscated.

According to prosecutors, the tunnel was located by US investigators on Friday.

During a surveillance operation, they followed suspects to a warehouse in the immediate vicinity of the border.

Examining the building, they came across the tunnel.

The cross-border corridor is built on one of the most fortified stretches of the US-Mexico border.

According to US data, 90 tunnels have been discovered under the border with Mexico in Southern California alone since 1993.

The corridors are often used for smuggling people and drugs.