US-Mexico drug smuggling tunnel found by police

US and Mexican officials have discovered a tunnel used by criminals to smuggle drugs across the California-Mexico border.

Building tunnels below the border is known as one of the drug cartels' preferred methods to expand their smuggling business.

The tunnel had lighting, ventilation and a rail system for moving drugs into the US.

US police also found some 20 tonnes of marijuana, while their Mexican colleagues seized around five tonnes.