this man heads special operations for the drug enforcement administration. >> if a mini mart is operating in our country's sending 40 million, 50 million, $60 million back, we're very earn canned about that. >> reporter: tens of millions of dollars. the bulk of the money, according to the dea, going to places like yemen, syria and lebanon. >> as state sponsorship declined, terrorism fueled by criminal activity is on the rides. >> reporter: while the dea acknowledges no smoking gun ties the drug money from the u.s. to terrorists, they say the existing evidence paints a clear picture. >> terrorists need money to finance their operations. they need money for logistics, recruiting, training. you cannot do that with american express and visa. you need a suitcase of cash. >> reporter: synthetic drugs aside, the global drug trade produces plenty of that. according to the u.n., some $300 billion and counting. synthetic drug use is are sowing in the united states accounting for more than 11,000 emergency