TUCSON – Three people are accused of trying to buy anti-tank weapons in Arizona for a drug cartel in Mexico. Federal indictments were recently unsealed  in Phoenix. Court documents show the three also tried to buy a Stinger missile. Click here to download the Indictment. The accused were trying to buy the military weaponry for the Sinaloa Cartel.  Court documents show they used pounds of crystal meth for a down payment on the weapons. The case started in 2009 in Phoenix. One of the accused, David Diaz, approached a confidential informant working for the Bureau of Alcohol, Tobacco and Firearms. They delivered nearly five pounds of crystal meth and $139,000 in cash. Then they brought ten more pounds to finish the arms deal. Robbie Sherwood is the spokesman for the U.S. Attorney’s Office in Arizona. “These are very serious charges, as the indictment that has been unsealed indicate. We will be proceeding to trial soon and we look forward to presenting our case at that time.” From the indictment: A Dragon Fire Anti-Tank Weapon, a Stinger Missile, (a surface-to-air missile like those used by Afghan fighters in the eighties to defeat the Soviets), two AT-4s, a shoulder-fired light anti-tank rocket, a variety of grenade launchers, two M-60 machine guns and three cases of hand grenades. Court records show that Diaz was trying to buy the weapons for the Yucatan Peninsula. They were destined for druglords Joaquín El Chapo Guzmán and Ismael El Mayo Zambada, the leaders of the Sinaloa Cartel. The cartel is battling not only every other cartel in Mexico, but also the Mexican Army. John Bailey, a Georgetown University professor who worked in Mexico most of his career, says this level of weaponry was likely designed to take on the Mexican government itself. “It’s the kind of weaponry that you’d expect to be used against the Army. These groups are willing to up the ante.” The trial begins in April in Arizona.