 In 2015, official reports of the U.S. government and the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) revealed that over the last years, Mexican cartels improved their firearm power, and that 71% of their weapons come from the U.S.Many of those guns were manufactured in Romania and Bulgaria, and then imported into the U.S.The Mexican cartels acquire those firearms mainly in the southern states of Texas, Arizona and California.