AYUTLA, Mexico—Masked men, rifles slung over their shoulders, stand guard on a lonely rural road, checking IDs and questioning travelers. They wear no uniforms, flash no badges, but they are the law here now.

A dozen villages in the area have risen up in armed revolt against local drug traffickers that have terrorized the region and a government that residents say is incapable of protecting them from organized crime.
The villages in the hilly southern Mexican state of Guerrero now forbid the Mexican army and state and federal police from entering. Ragtag militias carrying a motley arsenal of machetes, old hunting rifles and the occasional AR-15 semiautomatic rifle control the towns. Strangers aren't allowed entry. There is a 10 p.m. curfew. More than 50 prisoners, accused of being in drug gangs, sit in makeshift jails. Their fates hinge on public trials that began Thursday when the accused were arraigned before villagers, who will act as judge and jury.

Crime is way down—for the moment, at least. Residents say kidnapping ceased when the militias took charge, as did the extortions that had become the scourge of businessmen and farmers alike. The leader of one militia group, who uses the code name G-1 but was identified by his compatriots as Gonzalo Torres, puts it this way: "We brought order back to a place where there had been chaos. We were able to do in 15 days what the government was not able to do in years."
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