 Some researchers have asserted that most weapons and arms trafficked into Mexico come from gun dealers in the United States.There is also strong evidence for this conclusion, indicating that many of the traceable weapons come from the failed American government Operation "Fast and Furious", and there is a geographic coincidence between the supposed American origin of the firearms and the places where these weapons are seized, mainly in the northern Mexican states.Most grenades and rocket-launchers are smuggled through Guatemalan borders from Central America.