The June 30 press release from the Mexican Defense Secretary stated that military personnel had discovered a warehouse filled with armed men who opened fire on the troops. Soldiers repelled the attack, 22 “presumed aggressors” died - and just one soldier was wounded. The experienced Mexico staff of The Associated Press doubted the official story: 22 dead on one side, zero on the other seemed unlikely in a firefight. Correspondent Mark Stevenson set out for the warehouse in a remote area of the state of Mexico known to be rife with drug traffickers, and discovered evidence of a massacre. This series details what the AP investigation uncovered.