sentences:  Nigerian criminal groups are heavily involved in drug trafficking, shipping heroin from Asian countries to Europe and America; and cocaine from South America to Europe and South Africa.The large numbers of ethnic Nigerians in countries like India and Thailand give their gangs ready access to around 90% of the world's heroin.In the United States, Nigerian drug traffickers are important distributors of heroin, from importing it into the country to distribution level and selling it to lower-level street gangs.