Where does our ganja come from?

Wondering if anyone has studied this or any reporters have looked at this. The current college generation in South India (I know of TN and Karnataka both having this) smokes much more weed and much more socially than our parents did, but I am wondering where it comes from. In California before legalization their weed came from criminal groups and Mexican cartels. For us we are too far for it to come from Pakistan (I think?). But I was wondering who is the main producer and mover of the weed people smoke in TN? I have heard that our weed comes from Bangalore, but I don't know if anyone has looked into this and are reporting on how the weed is made? Are criminal groups profiting from this trade?