Much like his great uncle, revolutionary leader Pancho Villa, retired Mexican army Gen. Carlos Bibiano Villa Castillo isn't easily frightened.

Even before Villa started his job last month as top cop in the Caribbean coast state of Quintana Roo, he'd received a grisly welcome from Mexico's most ruthless drug cartel, the Zetas. 

The 62-year-old Villa, who shares the intense stare and strong features of his famous relative, is undeterred. He started his new job on April 5. ...