Well, apparently they're persecuting the Cult of Santa Muerte. Can't be sure, the Archbishop may have been part of a kidnapping ring. What I find fascinating is that it's tied to a gang that calls itself El Aztlan, referring to the mythical home of the Aztecs. That would be like a gang called the Atlanteans, esse! The culture is hooked into its mythos a lot stronger than mine is.
So the article mentions they also had these shrines built all along the road in Nuevo Laredo, and the government and the army went out and tore down the shrines. There's an ongoing war against the cult that's ratcheting up in intensity. Some will say it's another front of drug wars between the government and the cartels, but I tell you the truth, the war between the cartels and the government is really just another front of the spiritual war between the Powers and Principalities in high places, aww yeah.
But look, folks, there's a reason Mictecaciahuatl rules the underworld, and there's a reason she is Señora de las Sombras. I think they got too public with her, and her image became profaned. I think she's cutting off the impious, those who would use her image instead of honoring it. You don't fuck around with Aztec Gods. You just don't.