In Mexico, a country widely controlled by drug cartels, groups of armed vigilantes known as fuerzas autodefensas, or self-defense groups, have been rising up over the last year and in recent weeks have taken over communities in the state of Michoacan. The militia have surrounded Apatzingan, thought to be a key stronghold for the Knights Templar, controlling surrounding towns after violent street clashes as they move to weaken the hold of the Knights Templar on the region.

The state of Michoacan is a key trade hub, known for its rich farming land, producing limes, avocados and mangoes. Clashes...