Updated

Vigilantes who have taken up arms against drug cartel violence and common crime in southern Mexico announced Thursday they will bring charges ranging from organized crime to kidnapping and extortion against 50 men and three women who they have been holding prisoner at improvised jails.

Villagers armed with old hunting rifles, ancient pistols and small-bore shotguns set up armed patrols and roadblocks in the township of Ayutla almost one month ago to defend their communities against crime, saying authorities have failed to bring peace and safety to the Pacific coast state of Guerrero. So far, the state government has tolerated but not formally recognized the self-defense squads.

The growing movement toward self-policing, which has since spread to other towns in Guerrero, has sparked concern among human rights officials who say residents shouldn't be allowed to take the law into their own hands.

"What is happening in Guerrero state is a warning sign that should alert authorities to do their duty and guarantee public safety, to avoid having these (vigilante) activities grow and outstrip the power of official institutions," said the head of the National Human Rights Commission, Raul Plascencia. But in townships like Ayutla, it is clear the vigilante movement already has authorities cowed.

Villagers in squads of about a dozen patrol roads and search passing motorists, checking their identification against handwritten lists of "bad guys."

On Thursday, the unbound, unsmiling detainees were marched between rows of armed, masked vigilantes in the town square of El Meson, in the township of Ayutla. While the detainees appeared to be clean and adequately fed, and bore no obvious signs of mistreatment, reporters at the scene were not allowed to speak with them.

Two weeks before, angry villagers had turned back a team of Guerrero state human rights officials who had gone to visit the detainees and ensure they were being properly treated.

Human rights officials appear to be hamstrung; Mexican law allows rights commissions to investigate only abuses by authorities, not abuses committed by civilians against other civilians.

"We are not even sure if there are any authorities involved here," the head of the Guerrero state Human Rights Commission, Juan Alarcon Hernandez, said at the time.

Bruno Placido, the head of a community activist group and a leader of the vigilantes' movement, said the detainees, whom the movement refers to as "people under investigation" not prisoners, would be given a trial by an assembly of villagers.

But Placido did not say what procedures would be used or what kind of defense the detainees would be allowed to mount. "All that will be decided by the assembly," Placido said.

The trials are expected to start next week. However, the village is tightly patrolled and it remains unclear whether defense lawyers, rights officials or reporters would be allowed into the trials.

The town square of El Meson was crowded with villagers and local farmers watching the prisoner roll call Thursday; most of the detainees, who ranged from teenagers to adults, appeared to be from the same poor farmer stock as the villagers.

However, residents in Ayutla said drug gangs have been moving up from the nearby coastal resort of Acapulco, bringing cartel-style violence, kidnapping extortion with them.

Guerrero state Attorney General Martha Garzon Bernal told local media Thursday the vigilantes have no legal right to hold detainees, and said kidnapping complaints could be brought against them.

Since 1995, about 80 villages in Guerrero state have organized legally-recognized "community police" forces in which poorly armed villagers detain and prosecute people.

With their own jails, "courts" and punishments that can include forced labor for the town or re-education talks, the community police are usually recognized by state law. However, the self-defense forces in Ayutla don't belong to that system.