Koh Bak Kin was first arrested at Rome airport in 1976 with more than 20 kilograms of heroin and in 1978 was sentenced to six years in prison, where he met Mutolo. The already lenient sentence was further reduced, and Kin was released from prison in 1980. On his return to Bangkok, he was able to guarantee a steady supply of heroin to Cosa Nostra thanks to his links in northern Thailand with an emissary of the opium "baron" Khun Sa.