Mexican and South American cartels penetrating Australian border security to import tonnes of cocaine, underworld figure tells Four Corners

This man worked at Sydney Airport for several years, bringing in cocaine for the cartel. (Four Corners)

Mexican and South American cocaine cartels have corrupted people working within Australia's border security regime, at virtually every air and sea port in the country, according to an underworld figure who worked with them.

Four Corners spoke to the man as part of an investigation into Australia's cocaine market which found there's more of the drug in the country now than at any other time in history.