Three men have been arrested after the discovery of one of the most sophisticated tunnels for smuggling drugs from Mexico to the US. <br /><br />With lighting, ventilation and an electric rail system, US authorities are calling the underground passage a “super tunnel” – the fifth one they have found since 2010. <br /><br />More than half a kilometre of secret subway linked Tijuana in Mexico and the American city of San Diego, where the exit was inside a warehouse. <br /><br />The three men in custody are said to be drivers and have been charged with possession and intent to distribute drugs.<br /><br />Almost nine million euros worth of marijuana and cocaine were found inside the tunnel, which was closed down before any drugs made it onto the street. <br /><br />San Diego is a popular choice for underground passages because the clay soil is easy to dig.
