Two tonnes of cocaine have been seized by Colombian and Mexican police on a shipment bound for Sinaloa, Mexico.

The Colombian police found the narcotics camouflaged in 48 boxes of black zinc oxide, a compound used in printer ink.

A drug-sniffing Labrador called Mona first detected the cocaine at El Dorado airport in Bogota.

Once the powder had tested positive for cocaine, the Colombian authorities warned their Mexican counterparts which led to finding more 'black cocaine' at Mexico City airport.

Around 300 tonnes of cocaine are produced in Colombia each year, while 115 tonnes have been seized this year.